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February 9

Help (compter reboots after 20-25 minutes)

My PC works like dream when i do stuffs like surfing , watching movie etc but whenever i play any game it restarts after 20-25 min and keeps restarting with very soft beep (teep..) untill i switch it off for 15-20 min. i have cleaned the cabinet, reinstalled windows stil the probelm persists. all of my cpu fans are working 117.224.246.44 (talk) 06:55, 9 February 2012 (UTC)

Open the case carefully and clean it inside as well. Do the fans work particularly loudly? Do they usually work (as opposed to only working when the computer's under a full load)? Is the ventilation around the case sufficient?

Does the problem persist with any game, or maybe just with some of them? Do these games have a common denominator to them (to the best of your knowledge)? --Ouro (blah blah) 07:05, 9 February 2012 (UTC)

yeah one of my fan which i brought recently works a little loud but i dont think it is a heating issue because i once tried playing games with CPU cabinet open. — Preceding unsigned comment added by 117.224.246.44 (talk) 07:33, 9 February 2012 (UTC)

That can actually make the problem worse, not better, since it won't get very good airflow that way. RudolfRed (talk) 07:53, 9 February 2012 (UTC)

Cleaned the cabinet again.... Still no improvement 117.224.43.60 (talk) 08:50, 9 February 2012 (UTC)

Has it always been this way? If not, can you recollect any specific event after which the situation had worsened? --Ouro (blah blah) 11:08, 9 February 2012 (UTC)

This problem is occurring from last weak and i cant recall any specific event :( 117.225.24.139 (talk) 12:31, 9 February 2012 (UTC)

I agree with Ouro, knowing whether or not this problem persists with any game would be helpful. For example, if your computer crashes when you play a game like Battlefield 3, but it doesn't care if you play Plants vs. Zombies or a simple flash game in your browser, then it helps narrow down the possible causes. It could be that your computer only crashes when it accesses a second stick of RAM (which it might only need to do for demanding applications) that isn't properly seated or has gone bad. It could also be that these games cause your GPU to overheat because its fan has stopped working. You really need more specific information in order to diagnose the problem. Lhcii (talk) 18:29, 9 February 2012 (UTC)

Use one of those "system monitor" (maybe something is built into windows) utilities to check the cpu and gpu temperatures. The fan isn't the whole issue. Just a few days ago someone here had a cpu overheating because one of the heat sink clips was bent and the heat sink wasn't making good thermal contact with the cpu. You might also have something like flaky RAM. Try pulling the ram modules out of the board, cleaning the contacts with an eraser, and putting them back in, making sure to seat them firmly. 67.117.145.9 (talk) 19:46, 9 February 2012 (UTC)

While opening the case alone may not solve an overheating program, opening the case and pointing a box fan at the guts on HI certainly will help. Try that. Obviously this is rather annoying as a permanent solution, but will tell you if overheating is the issue. From the symptoms, it does sound like the graphics processor might be overheating. StuRat (talk) 04:57, 10 February 2012 (UTC)

I added to the title to make it useful. StuRat (talk) 05:00, 10 February 2012 (UTC)

Try CPUz and GPUz, they can make log files for you to look at to see whether anything was causing a problem or overheating just before the PC shuts down. You should also check and make sure that any BIOS settings for monitoring temperatures and fan speeds are enabled, I have a beep set if my CPU goes over 60 C, just in case something else fails to tell me of any problem that might be there. Chaosdruid (talk) 09:18, 10 February 2012 (UTC)

Trying to install GAP in Gimp

I just downloaded the Gimp Animation Package to use with Gimp, but I can't install it. The problem is that I cannot find the folder that's supposed to launch the setup (Gimp-GAP-2.6.0-Setup2.exe.). I downloaded the file from here, btw: ftp://ftp.gimp.org/pub/gimp/plug-ins/v2.6/gap/ 70.29.244.213 (talk) 09:10, 9 February 2012 (UTC)

F3 --190.60.93.218 (talk) 17:09, 9 February 2012 (UTC)

Why is my question not appearing on the page? 70.29.244.213 (talk) 18:15, 9 February 2012 (UTC)

Seems like this forum thread (http://www.gimptalk.com/index.php?/topic/28397-gimp-gap-260-for-windows/) is discussing the same issue you are having. There is a link to the Gimp-GAP-2.6.0-Setup2.exe you mention in the opening post. However, it seems that the 2.6.0 version isn't stable and they suggest that you download the 2.4.0 version, for which they also provide a link. I didn't read through the whole thread, looks to me like you'll find some helpful information in there though. Lhcii (talk) 21:48, 9 February 2012 (UTC)

Would this computer be ok for my purpose?

I am looking to purchase a smallish, portable laptop to take to class to take notes using, preferably the 2010 versions of, MS Word, Powerpoint and Adobe Reader. Would an old Mac with the following specs be ok? I will be transferring these notes from the PowerBook to my Windows 7 main PC laptop at home.

Apple Mac PowerBook 12" PowerPC G4, OSX 10.5.8, 1.33 GHz, 512 MB RAM, BUS Speed: 167 Mhz.

Thanks, Acceptable (talk) 09:51, 9 February 2012 (UTC)

Does the 2010 version of Office work on a PPC? The 2011 version says it will only work on Intel (in the system requirements section here). In addition, laptop batteries degrade with age - my 5 year old laptop's battery now only sustains the machine for a minute or two. Replacing the battery on the mac would probably obviate the savings you're looking for in buying such an old machine. -- Finlay McWalterჷTalk 11:15, 9 February 2012 (UTC)

(ec) Microsoft Office for Mac 2011 is probably the version of Office you will want. If its minimum required specification is anything like Office 2010, I doubt it will run acceptably on a 1.33 GHz, 512 MB RAM system. You can checkout the system requirements for Word 2011 and Powerpoint 2011. Astronaut (talk) 11:16, 9 February 2012 (UTC)

First requirement on the list: "A Mac computer with an Intel processor". A PowerPC G4 is not an Intel processor. It won't work. --Mr.98 (talk) 14:20, 9 February 2012 (UTC)

I'm sure you could make it work, but all of PPC, Mac, and hardware that old are asking for trouble. A similar vintage non-Apple computer for the same price will get you significantly more impressive hardware. ¦ Reisio (talk) 14:16, 9 February 2012 (UTC)

Agreed. It also doesn't help that the newer versions of Office run like crap on even new versions of the Mac. I would recommend using the iWork Suite instead, from personal experience. You can export to MS Office formats if you need to and can read them all. Office for Mac is a buggy, crashy, slow program. --Mr.98 (talk) 14:20, 9 February 2012 (UTC)

Hits on webpages

thepeerage.com gives one of my pages as a reference. I suspect as a result that page gets a lot of hits. How can I tell how many, preferably using cPanelX? Kittybrewster ☎ 12:56, 9 February 2012 (UTC)

You need to be able to read the access logs of the (virtual, perhaps) webserver instance that services your website. Either your hosting provider will have installed their own log analysis package or you'd download the logs and run an analyser (e.g. awstats) on them yourself. -- Finlay McWalterჷTalk 13:13, 9 February 2012 (UTC)

Thank you. Success. Kittybrewster ☎ 14:30, 9 February 2012 (UTC)

Grabbing frames of video

Resolved

How can I gram frames of video, (no I don't need a programm that asks to specific frame) I want to have half of the frames of all frames.. I found a programm called Video to image converter, It provides me exatcly what I want. the bad thing is that It doesn't support Matroska files (mkv). (PS: I remember I had a program similar who supported mkv files, but I'm not having good results with google, I just don't type the right keywords) --190.60.93.218 (talk) 14:23, 9 February 2012 (UTC)

DVDVideoSoft's website (http://www.dvdvideosoft.com/guides/free-video-to-jpg-converter.htm) lists the video file formats that they support in the footer. This includes .mp4, so I suggest that you convert the file into .mp4 first (http://www.afterdawn.com/guides/archive/convert_mkv_to_mp4_for_xbox_360.cfm) and then use your program on the newly converted file. Lhcii (talk) 19:42, 9 February 2012 (UTC)

ROfl it's funny you got the answer.. after Deep scanning my hard drive (because i was desesperate) I found a program called freevideotojpgconverter ohh yes! =) I'm so happy lol. — Preceding unsigned comment added by 190.60.93.218 (talk) 19:48, 9 February 2012 (UTC)

Why does the keyboard not match what it produces?

I am at a library. The key to the right of : says " above ' but produces @, and the key that says @ produces ". Also, the key that produces my signature (~) gives me ¬ instead. The key that should give me | gives me ~. Vchimpanzee · talk · contributions · 14:42, 9 February 2012 (UTC)

I expect the OS is configured for a different keyboard then is actually present on the computer. Perhaps a UK keyboard when it's a US one. Nil Einne (talk) 14:52, 9 February 2012 (UTC)

(ec) Sounds like the keyboard defined for that PC is a UK English keyboard. Go to 'Regional and language' settings in the control panel and make sure it has the correct keyboard and language settings. Astronaut (talk) 14:54, 9 February 2012 (UTC)

I talked to one of the librarians and he said they're getting new machines soon.Vchimpanzee · talk · contributions · 15:27, 9 February 2012 (UTC)

Seems like a drastic solution to a 2 minute fix in Windows. Astronaut (talk) 18:04, 9 February 2012 (UTC)

_{You're computers are damaged? oh don't worry send them to me! If they're so useless for you! 190.60.93.218 (talk) 19:50, 9 February 2012 (UTC)}

Which key produces which character is configurable in software. Which marking is physically printed on which key isn't. It would therefore be quite difficult to always ensure a full 1-to-1 correspondence between the two. JIP | Talk 21:21, 9 February 2012 (UTC)

Our article on Keyboard layouts show the different language keyboard layouts – which should back-up what has been said above. Changing the language keyboard layout should be an option available even to a library users. It should not be an admin only option. If you're blocked and can't change it, ask the librarian for the phone number of their IT support and create hell with them. If you can fix it yourself – do let the librarian know what a little smart-arse you are. He will then owe-you-one if you get any overdue fines etc. Depending on what version of windoz their using, you what need to find is the Language bar, third option along. Hope you find this is useful.--Aspro (talk) 22:25, 9 February 2012 (UTC)

Replying to Astronaut: the librarian saw no point in getting IT to do anything to computers that are being replaced. It's apparently not as simple as it sounds.Vchimpanzee · talk · contributions · 23:50, 9 February 2012 (UTC)

Could you not fix it yourself? As I said, it's a 2 minute job. Astronaut (talk) 11:49, 10 February 2012 (UTC)

Let's not jump to conclusions: the computers are not being replaced because the keyboard doesn't work. They probably are being replaced and no one is willing to invest any second on them anymore. Add to it that most people are helpless even when it comes down to simple fixes and that not averyone has an admin password at hand. — Preceding unsigned comment added by 83.36.33.29 (talk) 13:33, 10 February 2012 (UTC)

You want everyone and his brother at a library to be able to make changes? The person I asked read what was here and only said they weren't going to bother the IT people when there were upgrades planned.Vchimpanzee · talk · contributions · 19:09, 10 February 2012 (UTC)

A couple points:

1) They probably don't allow customers to change the keyboard layout, as that would result in practical jokers leaving it set to Japanese, etc.

2) If they are unwilling to fix it, I suggest just labeling the keyboard to match what it produces. I find that cutting off the sticky part of Post-It notes and placing them directly above the keys in question works for the top row (assuming a suitable gap between them and the function keys). This type of label can easily be removed, in case they reuse the keyboards with the new computers. StuRat (talk) 19:30, 10 February 2012 (UTC)

Vchimpanzee,  read and learn from Astronaut. Forget what the librarian has said. People, some of them foreigners, wonder into a library (as do mischievous school kids) and should they want to send an email back to friends and relativities in their home country – change the keyboard layout to what they are familiar with – but don't change it back before they leave! It would be daft not to allow their many users to do this. Travel the world and you will find many internet cafe's in cosmopolitan areas with keyboards set to different languages – (have you ever travelled out-side the US?). If their clientèle can change it – then so can YOU. As for the Librarian: Remember those times when everything was written on long scrolls of parchment? Well, this video clip shows a librarian of those times try to grasp new book technology. [1]. Watch, then see if you can make the connection with modern times. --Aspro (talk) 19:38, 10 February 2012 (UTC)

You can cycle through the various installed keyboard layouts by pressing ⇧ Shift+Ctrl. Repeat until the right characters appear when typing a key. — Edokter (talk) — 19:46, 10 February 2012 (UTC)

Thank you. If I manage to end up on the same computer next time I am there, I will try those last two ideas. If someone else is on it, I won't.Vchimpanzee · talk · contributions · 20:29, 10 February 2012 (UTC)

And I am here. Let me see what happens.Vchimpanzee · talk · contributions · 14:35, 15 February 2012 (UTC)

There must be more to it than ⇧ Shift+Ctrl. That's not doing anything. On the other hand, the video was captioned, so I was able to appreciate it with no sound. Thanks for that. They would expect me to provide my own headphones.Vchimpanzee · talk · contributions · 14:45, 15 February 2012 (UTC)

Well the default for Windows 7 seems to be left shift+alt to me. However rather then fooling around with shortcut keys, I would have first tried the control panel which for whatever reason you don't seem to have done. I take it the language bar is not floating or docked on the taskbar (should show up as a a EN or whatever code for the language and/or a keyboard). Nil Einne (talk) 22:24, 15 February 2012 (UTC)

I explored other options but they didn't work either. But it's a library and the control panel is off limits.Vchimpanzee · talk · contributions · 23:34, 15 February 2012 (UTC)

Simple question I hope

Resolved

Whenever I download any PDF from an online source (which is like five times a day) instead of opening it saves and I have to go find it in the download folder and open it. I could swear it used to open without this extra step. I imagine it's a settings issue but I don't know if the setting is in my computer or the browser I use or the PDF program I run. I am on a Macmini running Snow Leopard I think. I have Adobe Acrobat Professional 8 and I use Firefox. Thanks.--108.14.197.46 (talk) 19:50, 9 February 2012 (UTC)

Firefox gives you the option to always handle files of the same type the same way. At some point you must have chosen the 'Save as' option rather than the 'Run' option and also told Firefox to always save files of the same type (PDF). In order to change this setting and restore the way it handles PDF's to the default, navigate to Tools>Options in Firefox, then click the 'Applications' tab. There should be a few listings on the left side for 'Adobe Acrobat Document', you need to change the drop-down on the right to 'Use Adobe Acrobat' or 'Always ask'. Note that I am giving you these instructions from version 10.0 of Firefox on Windows XP, so there may be disparity in the instructions. Lhcii (talk) 20:10, 9 February 2012 (UTC)

Done. It works. Will save me lots of time (over time). Thanks!--108.14.197.46 (talk) 21:03, 9 February 2012 (UTC)

Telling if a company is legit

How can I tell if this company is legit? Charter Global. They sent me a recruitment email and the job looks interesting but I do not want to get scammed. 68.232.119.30 (talk) 21:33, 9 February 2012 (UTC)

Nothing I have found looks particularly scammey. Suggest you email them back and ask them how they found you -which is a reasonable question to ask- and say your interested. Being wary is wise but at the same time it might by legit. I think you (we) need more information before you (we) can make that judgment.--Aspro (talk) 22:07, 9 February 2012 (UTC)

If you're being wary, how do you even know the mail came from them? Isn't it still the case that it's trivial to send a mail purporting to come from someone else? I suppose if the return mail is to a checkable domain name then at least you know where you are replying to... 86.183.2.20 (talk) 22:28, 9 February 2012 (UTC)

If they really are trying to recruit you, there's no reason they should be asking for money or credit card numbers. If they ask for those, it's definitely a scam. What could be trickier is if they say they want to do a background check, so ask for your social security number, birth date, etc., which could also be used for identity theft. I'd be rather suspicious if they ask for that info before they meet with you in person. StuRat (talk) 04:49, 10 February 2012 (UTC)

Reply directly to charter Global, through their web page if you are interested. Also check past versions of their web-page through archive.org, that will get you an idea of the organization that they are. — Preceding unsigned comment added by 83.36.33.29 (talk) 13:36, 10 February 2012 (UTC)

ActiveX in IE9 / Win 7

Hello!, under what circumstances does IE 9 prompt for websites to run ActiveX (assuming default security settings)? I have Flash installed, and that seems to run on any website without prompting. Yet when I go to http://ie.microsoft.com/testdrive/browser/activexfiltering/Default.html I am prompted "This webpage wants to run the following add-on: 'Windows Media Player' from 'Microsoft Corporation'". However, when I look at the list of installed add-ons, Windows Media Player is already there, installed and enabled, just like Flash, and even appears in the list of add-ons that can "run without permission". Why am I prompted in one case but not the other? What is the difference?

Furthermore, if a website wanted to run a brand new ActiveX that I did not even have installed, then what would happen? Presumably big red warnings and alarms? For fairly obvious reasons I do not want to seek out websites with unknown ActiveX content to test this...

I would be extremely grateful if anyone could shed any light on this. I cannot find any useful explanation in Microsoft help. 86.183.2.20 (talk) 22:25, 9 February 2012 (UTC)

How to remove screwdriver head from Milwaukee Shockwave socket set?

I have a Milwaukee Shockwave screwdriver and drill bit set, and I have a small screwdriver head stuck in the hex socket that fits into a drill chuck or screwdriver body - it seems to be locked in there, and I can't figure out how to remove it - any ideas? THanks! — Preceding unsigned comment added by 184.76.48.158 (talk) 22:34, 9 February 2012 (UTC)

These are good tools. Rather than ask here (where you’ll get suggestions like -dip it into liquid nitrogen and it will simply contract and drop out) contact Milwaukee direct. After all, you have paid a premium for quality and thus your entitled to after-sales service that a Chinese back-street work-shop wont give you. See here:[2]--Aspro (talk) 22:50, 9 February 2012 (UTC)

Thank you - I will call them tomorrow, but they are closed right now - I wondered whether there was something obvious I was missing, like twisting the chuck or something. — Preceding unsigned comment added by 184.76.48.158 (talk) 22:53, 9 February 2012 (UTC)

OK - got it - you just have to REALLY pull them - there is a strong magnet in the base. — Preceding unsigned comment added by 184.76.48.158 (talk) 23:24, 9 February 2012 (UTC)

Resolved

Help with Regular Expression (Syntax Searching) Please?

Hello, I'm using a custom word filter, and it uses Regular Expressions.

I'd like to filter out (match) "angst" regardless of type case, or if a 'y' is added after it to become 'angsty.' So that whether it is AnGsTyfjdL or anything else it will still get matched and filtered. Going to do this for a bunch of meaningless adhoms. Hopefully this example will be enough to teach me what I need for all of them. Thank you very much. --68.117.130.106 (talk) 23:30, 9 February 2012 (UTC)

what tool will you be using for the search? If it's grep, you can do "grep -i -e angst -e angsty". The -i makes it ignore case and each -e is a pattern to search for. RudolfRed (talk) 23:45, 9 February 2012 (UTC)

(?i)angsty|angst     -- Finlay McWalterჷTalk 23:46, 9 February 2012 (UTC)

I'm not using Grep, but doing -i did work. Thanks a lot. --68.117.130.106 (talk) 02:20, 10 February 2012 (UTC)

February 10

USB 3 external hard drive

I see external hard drives (HD) that use USB 3.0. My computer has USB 2.0. As I understand it, USB 2.0 speed is slower than the transfer rate of a HD but USB 3.0 is faster (than the HD transfer rate). If I put a USB 3.0 card in my computer, a USB 3.0 external HD would be faster than a USB 2.0 one, right? Would the transfer speed of an external USB 3.0 HD be close to that of an internal HD? Bubba73 ^{You talkin' to me?} 00:28, 10 February 2012 (UTC)

See List of device bit rates#Peripheral. Answer is basically yes. Moondyne (talk) 04:22, 10 February 2012 (UTC)

Resolved

Thank you. Bubba73 ^{You talkin' to me?} 05:09, 10 February 2012 (UTC)

Computers showing incorrect bit rate of songs question

I recently downloaded a song that was around 3 minutes long and was over 8 MB, which for that length in that size would be at 320 kbps, but when I right clicked the audio file, then clicked the properties options, and then clicked the details tab; I saw that it said that it was 192 kbps, which I know is incorrect. It should say 320 kbps based on the size and length. Also, I noticed there have been many past circumstances where I would download a song that was not 320 kbps, 256 kbps, 192 kbps, 160 kbps, nor 128 kbps, but a kbps between those numbers like 260 kbps or 172 kbps for example. However, when I looked at the Details section of Properties, the computer would register it at 320 kbps instead. So, why would the computer sometimes display the wrong bit-rate of songs? Is it the computer or does the error have to do with the way an audio file was compressed or made? What causes these errors? Willminator (talk) 01:29, 10 February 2012 (UTC)

Many audio files use a variable bit rate. It sounds like you are asking for an average bit-rate, which seems like the most intuitive measure of a VBR file; and your program is displaying "something else" (perhaps, bitrate of the first compressed frame, or bitrate identified in the ID3 tag, which might be incorrect). Nimur (talk) 03:14, 10 February 2012 (UTC)

Slow computer

Over the last week, my computer has been very slow. This suggests to me that perhaps something is running in the background. How do I determine if something is doing so and how do I get rid of things I don't want to be there? I haven't downloaded anything other than my emails 72.136.132.216 (talk) 02:17, 10 February 2012 (UTC)

Sorry, I forgot to add that I am running XP. 72.136.132.216 (talk) 02:21, 10 February 2012 (UTC)

I think this works on XP: do ctrl-alt-del and start the Task Manager. Click on the Processes tab. Then the CPU column will show you what percentage of the CPU each process is using. You can click on the CPU heading to have it sort them by CPU usage. Bubba73 ^{You talkin' to me?} 03:02, 10 February 2012 (UTC)

Almost. The "CPU" tab has some weird two digit numbers, most of which are 00. There's a "CPU Time" column which does what you said. You need to click on it twice to sort in descending order. Of course, CPU time might not be the limiting resources, so the "Mem Usage" column and others should be checked out, too.

Then, if you find some process you can't identify taking up an inordinate portion of the resources, kill it and see if things improve or if it manages to restart. If, on the other hand, some process you actually need (like your browser) is the culprit, then you might need to reinstall that app to get rid of whatever has infected it. You could try running some anti-malware progs first, like AdAware and Spybot Search & Destroy. StuRat (talk) 04:41, 10 February 2012 (UTC)

Those two-digit numbers in the CPU column are the percentage of the CPU that the process is using. The "CPU time" column is the CPU time it has used since it has started. I'd look first for something using a high percentage of the CPU (unless something is accessing the HD a lot). Bubba73 ^{You talkin' to me?} 05:12, 10 February 2012 (UTC)

Thanks everyone. I will go through these steps. I frequently run spybot and will do it again before I try these steps.

72.136.132.216 (talk) 17:20, 10 February 2012 (UTC)

Xbox 360s Hdd

Hi, I have an Xbox 360s with a small hdd, I want to buy a new one that has more storage, but I noticed that all the drives are internal. So, I had two questions: is it hard to install the drive? And can I keep the original drive and run it alongside the new one, or will I need to somehow remove the old drive, install the new one, and transfer everything to it? Thank you for any help:-) — Preceding unsigned comment added by 209.252.235.206 (talk) 05:50, 10 February 2012 (UTC)

See our article section Xbox 360 accessories#Detachable hard drives. The drive is a 2.5" notebook drive that's encased in a proprietary case and has proprietary firmware. Here is Microsoft's article on how to use a proprietary transfer cable to copy the contents of the old hard disk from the new one — though I think this article is about the old-style Xbox hard disks, not the "S" disks. Comet Tuttle (talk) 00:57, 12 February 2012 (UTC)

No need for extremely complicated passwords

The advent of brute force and dictionary-based password cracking has compromised many computer systems, e-mail accounts, etc. thanks to the raw computing power of advanced password crackers. The usual response has been to ask people to make up ever longer and more complicated passwords, which in turn may be forgotten by the users.

However, I've thought of a far simpler way, which would both help users stay with relatively simple passwords and solve the brute force cracking problem virtually forever: why not design all computers and encryption systems such that, if you type the wrong password, you have to wait for five seconds before you can type the password again? It would only be a very minor inconvenience for human users, but it would immediately render useless the raw computing power of advanced password crackers, regardless of how performing they may become in the future - who cares if your password cracker can calculate one billion passwords per second if it can only enter one password every five seconds? Even dictionary-based attacks with a relatively small search space would take decades or even centuries to carry out.

So... Is there a technical reason why this has not been done everywhere, or has nobody ever thought of it before? Leptictidium (mt) 10:35, 10 February 2012 (UTC)

It's a technique already widely used; as is allowing only a certain number of incorrect guesses before locking the user account and requiring an admin reset. --Tagishsimon (talk) 10:41, 10 February 2012 (UTC)

Well yes... Maybe I worded my question poorly. My question is "Why is this not done everywhere"? Leptictidium (mt) 10:42, 10 February 2012 (UTC)

That's how it works already. Massive dictionary cracking is mostly done when someone has stolen a copy of a password database and is cracking it on their own computer. -- Finlay McWalterჷTalk 10:42, 10 February 2012 (UTC)

(EC with below) Also the OP doesn't appear to understand how password cracking works. You can't design a local encryption system such that if you type the wrong password you have to wait 5 seconds. If you enforce a software limitation, this is fairly pointless since anyone who wants to crack the password will just break the software to remove the limitation. Actually few would brute force by trying to use the program anyway, this imposes unnecessary interface limitations.

What you can do is make the computation expensive and this is sometimes done. However this is not going to guarantee it will take 5 seconds per password. Someone trying to break the password is likely to have access to far more computing resources, so will be able to do far more then one per 5 second. (You'd generally not want it being much more then 5-10 seconds even if the person has some junky slow old single core.) Worse they may be able to use the GPU or dedicated hardware to vastly speed up computation (possibly in the order of 200x of more) if they're really interested.

And while this works for local passwords, it doesn't work for remote ones (where the server serves many users) since if the computation is very expensive this means it will be very difficult for the company to serve many users without spending a large amount of resources. As FM said, most companies will impose limitations on the frequency or number of tries per account which since it's remote. you can't avoid. But this doesn't help you if the database is stolen. When people do bruteforce passwords on remote computers, they usually rely on parellisation of accounts. (Actually most do this all the time.)

Nil Einne (talk) 13:25, 10 February 2012 (UTC)

Something to be aware of when enforcing a waiting period is that it can be used for denial of service. And the concept is not applicable to encryption, where the premise is that about everybody could have access to the encrypted data and you would remain safe. If it takes only 5 seconds per password to check if it was used for encryption then it takes less than 60 computers to check for the million most common passwords in 24 hours. --145.94.77.43 (talk) 13:11, 10 February 2012 (UTC)

How to create a range of passwords that don't get confused or forgotten

Hi. The above question made me think of this one. Like most people, I use a range of different passwords for different machines, websites, software etc. The ones I use often, I tend to remember, but the others get confused or forgotten.

Worse, some of the passwords I need to use have to be changed regularly, and the system won't allow old passwords to be used.

I don't want to do anything unsafe, like write them down or use just one for the lot of them.

I guess this is a common problem for techies (not me, you! This is the reason for posting here, rather than at the Misc board) so, I'm wondering if you know of any tips out there for creating suites of easy to remember safe passwords. --Dweller (talk) 10:57, 10 February 2012 (UTC)

I use Keepass to generate and store insanely un-memorable passwords. -- Finlay McWalterჷTalk 10:59, 10 February 2012 (UTC)

Sophos suggest generating a nonsense word that you can easily re-generate from scratch each time you need it. See here. On the other hand, xkcd suggests using dictionary words in unusual combinations, like this. - Cucumber Mike (talk) 13:05, 10 February 2012 (UTC)

So now you know, when hacking into a geek's computer, forget trying pet names, go straight for correcthoresebatterystaple. Works every time. - Cucumber Mike (talk) 13:18, 10 February 2012 (UTC)

If it's just for web sites, Firefox's built-in password autofill feature works pretty well. Otherwise, there are various password manager programs you can use. Generating passwords can be done with a "key derivation" function like PBKDF2. You'd choose a "master password" from which the others are generated, and use the name of the web site you want to log into as the salt. 67.117.145.9 (talk) 00:11, 11 February 2012 (UTC)

Hello again. I often use computers that I cannot add software to. Not only that, but the passwords I need to use are often ones that give access to the computer itself, as well as websites etc. So for these reasons, your suggestions don't really help. Are there any good mnemonic devices you've come across that help generate multiple memorable but safe passwords that don't get confused? --Dweller (talk) 16:53, 14 February 2012 (UTC)

How can I tell if I have USB 3.0?

How can I tell if my computer has USB 3.0? I think it is only USB 2.0, ut I want to check. I tried control panel/system, Speccy, and Belarc Advisor, but none of them seem to say. Bubba73 ^{You talkin' to me?} 17:14, 10 February 2012 (UTC)

Open Device Manager (Start -> Control Panel -> Performance and Maintenance -> System -> Hardware -> Device Manager). Look for the entry for Universal Service Bus Controller and expand it. If you see 3.0 mentioned, you're all good. If not, look for 'Super Speed', which indicates USB3.0. 'High Speed' or 'Enhanced' denotes USB2.0. If you don't see any of these, you can right click on each entry, choose Properties and then click the Advanced tab. Again, you're looking for 'Super Speed' for USB3.0, or 'High Speed' for USB2.0, like in this picture. Bon chance! - Cucumber Mike (talk) 17:38, 10 February 2012 (UTC)

An alternative is to figure out which USB controller is installed and look up its capabilities. For example, Device Manager (on Windows 7) reports my machine has an Intel 631xESB/632xESB I/O Controller Hub. Reading the datasheet for that one sees that it supports eight USB2.0 ports (but no USB3). Doing the same for any machine should be similarly straightforward. -- Finlay McWalterჷTalk 17:42, 10 February 2012 (UTC)

Resolved

Thanks, I don't see anything that says 3.0 or Superspeed. I do see "hub is operating at high speed", so it must be 2.0. Bubba73 ^{You talkin' to me?} 23:30, 10 February 2012 (UTC)

TV brightness

I have a perpetual problem with night scenes viewed on Netflix streaming being too dark to see on my CRT TV. No doubt most of the problem is at their end (either when a digital recording is first made or when converted to streaming digital), but I'd like to also be able to fix it at my end. This is what I've done so far:

1) Turned off all the lights and installed black-out drapes to darken the room.

2) Turned the brightness and contrast to max on the TV.

While these help, it's still impossible to see anything at times. I'd also consider getting a new TV. However, the "brightness" rating they give seems to be how bright it is when displaying a white scene. What I need to know is how bright it can be made when displaying a dark scene.

A) How can I get this info before making a purchase decision ? The only way I can think of is to hang out in showrooms and wait for very dark scenes to appear, then trying to compare models. Of course, this would only allow me to compare them at their current settings, as I'm not likely to be able to turn the brightness and contrast to max in the showroom.

B) Also, would a computer monitor used as a TV generally be better, worse, or the same as a regular TV, in this respect ?

C) How would the format, such as CRT, LCD, DLP or plasma compare ?

D) Would a dynamic contrast ratio help (where the back-light level is adjusted depending on the scene) ?

E) Any other suggestions ?

StuRat (talk) 19:42, 10 February 2012 (UTC)

Regarding A, TVs in the showroom will invariably be already set to max brightness/contrast, in order to make them seem as vibrant and eye-catching in a brightly lit store. This setting is typically inappropriate in an actual home viewing setup, and having the contrast too high may be a major part of the problem you are suffering.

D may help, but I would have thought it unnecessary in a darkened room.

To get everything set up well at your end I would recommend using a calibration disc. Many DVD and blu-ray movies will actually have this function, so it may not even require a special disc if you already have such a film in your collection - for example this page discusses the item on THX labelled DVDs. You could also check the manual for your TV set, as some models are capable of displaying built-in test patterns. AJCham 00:38, 11 February 2012 (UTC)

Thanks so far. Any other suggestions ? StuRat (talk) 02:54, 13 February 2012 (UTC)

no isp

1) if you dont have an isp, is there a way to hook a pc to a phone jack and use the internet? thanks, jake (p.s. i forgot my password, to here and my email. must. kill.) 70.114.254.43 (talk) 23:55, 10 February 2012 (UTC)

2) also, two more quastions. can you write a program that starts itself?

3) and, how do i block sites with the hosts file on windows 7? thanks again, jake 70.114.254.43 (talk) 00:02, 11 February 2012 (UTC)

I numbered your questions for you:

1) Not really, although some ISP progs will let you use them for free for a bit to test them out.

2) No, but you can have a program that's started at boot-time by the O/S, then stays dormant until it decides it's time to do something. StuRat (talk) 00:12, 11 February 2012 (UTC)

thanks sturat. 70.114.254.43 (talk) 03:49, 11 February 2012 (UTC)

For a couple of decades at the end of the second millennium, when they had phone lines but didn't have normal Internet yet, you could connect a computer to a PHONE line (a physical phone line), have it make a call (make phone tones, as if it was placing a call), another computer would answer, and then they would "talk" (over the phone line) and you would get Internet at like 0.05 megabits. It cost almost as much as a phone line itself costs (you paid to the company owning the computer that "picks up"), but of course you also had to pay your own phone company (what today would be an ISP) so you would have your own phone line and any charges you accrued at the same rate as a real voice call on that line (so some people paid by the minute, some people got a free local number service from their phone company, didn't have to pay extra locally on their land line phone). I don't know how the companies that picked up the phone when your computer called got on the Internet though, as it seems this just wouldn't scale. There had to be something else, as obviously they didn't have a phone line between your Internet company and every web site you access, so I dunno. --80.99.254.208 (talk) 09:36, 11 February 2012 (UTC)

As an interesting point, I heard that AIM started out as this kind of service too. I forgot to answer your original question, but I heard that some people were still paying AIM even though there's already home Internet, (which is a joke), but you should look it up. It should be possible to pay for AIM, and then dial in on a LANDLINE from your computer and have it talk to aim and get the Internet. It probably works on a cell phone too, but unless you have unlimited minutes you better watch out. Maybe AIM has made this a free service by now, I don't know. The point is, it should be possible to get on the Internet using nothing but a phone if you don't have an ISP. --80.99.254.208 (talk) 09:40, 11 February 2012 (UTC)

Are you talking about a dial up ISP? Or just basic modem communication? The early days of ISPs were bulletin board systems (BBSs), the more progressive of which would have an internet link. But, while this is kind of tautological, if you're connected to the internet, however you're connected is your ISP. So no, you can't get on the internet if you don't have an ISP. Shadowjams (talk) 23:29, 11 February 2012 (UTC)

Another point... I'm going to start feeling old here, but by AIM I assume you mean AOL, which was a large intricate online community (like a BBS) that began to add internet connectivity. By the time of the AOL Instant Messenger I think they offered internet access to all their customers. AOL did indeed have dial-up computers, and I suspect most people here over 25 remember the familiar modem tones when they connected with their modem. Shadowjams (talk) 23:32, 11 February 2012 (UTC)

WRT the hosts file, the path is c:\windows\system32\drivers\etc. The HOSTS file has no extension; there may also be a example version hosts.txt - make sure you don't edit the wrong one. You can edit it using notepad, but will need to do so using an Administrator account. The HOSTS file contains examples, but you can add something like:

127.0.0.1 www.site-to-block.com

which will redirect attempts to visit www.site-to-block.com to the localhost. --Kateshortforbob _talk 11:29, 11 February 2012 (UTC)

How does ISP Work? How they connect all computers of the world with mine? 190.60.93.218 (talk) 12:30, 15 February 2012 (UTC)

February 11

Status of the internet

Is there a page where I can view the live status of the internet, like the global sea cables and stuff? 62.143.31.173 (talk) 17:05, 11 February 2012 (UTC)

http://www.internetpulse.net/ ? ¦ Reisio (talk) 17:20, 11 February 2012 (UTC)

"Appearance" of the identity function

To quote Nothing:

To instruct a computer processor to do nothing, a keyword such as "NOP" may be available. This is a control abstraction; running processors are always computing something, if only the identity function.

Reading Identity function, I'm not exactly sure what this is. What does the identity function "look like"? I'm imagining that the computer writes this function to a document until there's enough to cover a single printed page. How would the finished page appear? Nyttend (talk) 18:44, 11 February 2012 (UTC)

The passage is not very well worded. What it is really trying to say is that a running CPU is constantly executing machine language instructions, one per instruction cycle. It may be executing instructions that have no effect, but it is still, in each cycle, executing an instruction and then moving on to the next instruction in the currently executing program. — Preceding unsigned comment added by Looie496 (talk • contribs) 19:36, 11 February 2012‎

I've heard people use this fact to suggest that it doesn't matter how much you're computing in relation to heat from the processor... which is not at all true with modern processors since they change voltages and scale down their operations in response to load. But that's an aside... Shadowjams (talk) 23:26, 11 February 2012 (UTC)

In the original 8086 instruction set (and probably the rest of the x86 derivatives), the NOP instruction is opcode 0x90. The rest of the 0x91-0x97 opcodes are things like XCHG BX AX; XCHG CX AX; XCHG DX AX, etc. In fact, all of the original user-modifiable 8086 data registers are there, except for register AX. From how things are laid out one can deduce that the NOP opcode is actually the "missing" XCHG AX AX instruction. That is, exchange the value in register AX with the value in register AX - effectively a do-nothing operation. As modern processors use microcode, though, so the internal implementation of the NOP operation is unlikely to still be XCHG AX AX. The other issue is that modern computers typically do multitasking, so most often when a program has nothing to do, it hands execution over to the OS and says "wake me up in 100 ms". The OS then hands out the extra available time to other programs running on the computer. If there's absolutely nothing that the computer can be working on, there's usually a "system idle loop" somewhere in the OS where the OS then obsessively checks for any new work "did he move the mouse? type on the keyboard? any network activity? ..." There may be some NOP opcodes in the loop to slow things down, but I believe most modern processors have the ability to throttle their execution speed, saving energy, so instead the OS would tell the processor to slow down until you need the speed again. -- 67.40.215.173 (talk) 01:10, 12 February 2012 (UTC)

The same system of interrupts it uses to say "wake me in 100ms", it can also use to say "wake me when you get input" or "wake me when you finish reading from the hard drive", so the OS doesn't need to poll for activity ("obsessively checking for new work"). Also, preemptive multitasking is much less failure-prone than cooperative multitasking, so programs get kicked off the CPU every once in a while whether or not they think they're done. Paul (Stansifer) 04:57, 12 February 2012 (UTC)

I'd say that the passage is misleading. The identity function is a function, so it takes an input and produces an output (in this case, the same value). This works to describe NOP, if you think of opcodes as functions on the state of the whole machine ... but people don't typically think of machine code that way, unless they're trying to do some kind of software verification. Paul (Stansifer) 04:57, 12 February 2012 (UTC)

When there's absolutely nothing to do, HLT. It's basically an infinitely long NOP. That's what you'll find in the idle loop of a multitasking OS if you look deep enough. It's the original (and simplest) power-saving interface. Also, I agree that "identity function operating on the machine state" is a definition of NOP that only a pure mathematician could love. 68.60.252.82 (talk) 11:39, 12 February 2012 (UTC)

Except that a NOP is not an identity function in that context since instruction pointer gets incremented. --145.94.77.43 (talk) 17:53, 12 February 2012 (UTC)

It's evident that our article contained some poetic abuse of notation. I recommend we change the wording and remove the term "identity function." Whether that term is valid or not, it's uncommon at best, and misleading at worst. I'll rewrite the article section if it's not done already, after consulting a reference.. Nimur (talk) 23:49, 12 February 2012 (UTC)

Limited WiFi Access

Hello. Is it possible for restaurants to limit WiFi access? If so, how can clients be tracked for the amount of time online? Can't be IP addresses, eh? Thanks in advance. --Mayfare (talk) 23:51, 11 February 2012 (UTC)

Yes. Probably by mac address 82.45.62.107 (talk) 00:09, 12 February 2012 (UTC)

Another way is to change a password daily, and publish it in the restaurant so that only genuine patrons can use it. Graeme Bartlett (talk) 10:14, 12 February 2012 (UTC)

Yes I think this is a more likely possibility then by MAC address for a restaurant or other similar scenario. Another common method is to print a ticket/voucher with an access code that's likely entered in to a captive portal. A ticket/voucher can then be provided on request to patrons, provided to customers with every order or even integrated in to the receipt system so one is given with every receipt. In this case since each customer gets a unique access code you can easily limit usage per customer if you feel is necessary. (You can try to do this with MAC address but it's trivial for a technically competent person to change on many laptops.) Nil Einne (talk) 12:42, 12 February 2012 (UTC)

But changing the MAC address doesn't get you anything if you are giving privileges (rather than removing them) per address. It's how I would do it: have them input a code, record the MAC address in a list of allowed addresses, drop the MAC address from the list when the time had expired. I don't know what else you'd use to guarantee that you were reliably granting access to the correct machine, anyway. --Mr.98 (talk) 03:42, 13 February 2012 (UTC)

Sorry for the confusion, if it wasn't clearly, I was largely talking from the restaurant's POV. In particularly when I mentioned MAC address in my last sentence, what I meant was if you used a used a MAC address to automatically limit usage per user, in a system where there was a common password. (I was making a distinction between a system with unique codes and a system with a common passwordl and pointing out what was possible with unique codes that was difficult to simply but reliably implement with a common password.) As for your statements, I'm not quite sure what your describing.

If you are describing a scenario where you have a common password (perhaps one that changes daily) and you ask the user to connect and your router shows which MAC addresses have recently tried to connect (hopefully only 1!) and manually allow it; remember we are talking about a restaurant and similar scenario where the staff may not be particularly competent and even if they are you likely don't want them spending much time on such a thing. (You can automate this by allowing all that tried to connect in the last 30 seconds or something when you push a button but this has a slight increased risk of enabling access to people you don't want and probably of greater annoyance this requires the staff and customer to semi-coordinate.)

Remember what the restaurant or whatever probably doesn't want is Joe the barber in the neighbouring shop using their wifi when he has no customers. Let alone the customers in the next door cafe where they don't have wifi. This could perhaps be implemented by a single common password that changes daily but in such a case the barber or neighbouring shop only needs to get it once each day. (If someone comes inside, you could refuse to serve them or even serve them with a trespass order but that gets a bit complicated as would any lawsuit for misuse over your wifi.) A unique code per customer with a time and perhaps also data limit makes this a lot more difficult and can be implemented in a system where the only thing the staff have to do is perhaps push a button to generate a voucher, or even just give the customer their receipt. And all the customer has to do is enter that code in to a captive portal. It also means that in less formal restaurants and cafes where it's connected to an order, people can't buy a drink and then hang out for 4 hours if you don't want that.

Internally the way the router enables access is probably by automatically allowing the MAC address of a device which enters a valid code, if this is what you meant then your technically correct. But the point is you still need the unique code. If you only allow one MAC address per code, whether you claim the access is limited by MAC address or by the code is largely a matter of semantics, and the technicalities will depend on the device. (I suspect most devices actually do it at the code level, obviously the router needs to drop the MAC address after the time limit is reached but this would be tied to the code.) Although from the restaurants POV, all they really need to know about is the code.

However it may be the case that you'd prefer to allow multiple devices per code, e.g. so the customer can use a smartphone, tablet and laptop without needing multiple codes. Or if the restaurant is the sort where you generally only get one order, a party with multiple people will probably want each person to have access. While this does cause additional risks. E.g. the barber could go dumpster diving or ask customers who leave if they can have the code. And if the device limit is very high, the competitor restaurant could send someone to get a new code every hour or whatever. And perhaps of greater concern in a less formal scenario one or two customers of a large party could order coffee and everyone could use the internet access which you may not want.

Nevertheless in some cases it may be an acceptable tradeoff rather then needing to generate multiple codes per person, or at least one for each person in a party. Apparently not all systems support this, e.g. pfSense didn't or at least not concurrently [3], not sure about m0n0wall. But if it is supported, then it's almost definitely the case that you want the time limiting to happen at the code level, otherwise we get back to the scenario where the customer can simply change their MAC address and continue to use the code past your allowed time limit and any data limit that exists (and of course so could your barber). In other words, while the way the router controls access may still be by automatically allowing the MAC address of any device which enters a valid unique code, the way it carries out accounting would be by code.

Nil Einne (talk) 20:00, 13 February 2012 (UTC)

February 12

Firefox and cookies (yet again)

Admittedly, I'm probably more paranoid about online security than I need to be; here's the situation I've put myself in. I'm on FF9, but this behaviour hasn't changed in many releases.

My cookie settings are: "Accept cookies from sites" is ON, "Accept third party cookies" is OFF, and "Keep Until" is "Ask every time" -- which means I get prompted for a LOT of cookies. Mostly, I'll Allow For Session, but the Google Analytics __utm-series, I deny -- hold down Alt-D until it stops trying (sometimes 20 or 30 attempts!)

And, about half the random sites I visit HANG at that point, with the message "Reading google-analytics.com" in the lower left corner. Note, this is NOT the "Transferring from.." message. Progress indicator keeps circling. My usual response is to stop the page load, then shift-reload. Sometimes several times until the whole pages loads, and sometimes it just never does.

(Finally, we're getting to the questions:) BUT, if I simply click Deny for Site at the beginning of the session, the page loads fine. AND, if I use the private browsing features, it loads just fine. WHAT'S the difference between denying individual cookies, and denying them site-wide, that causes a site or google-analytics itself to hang on one and not the other?

--DaHorsesMouth (talk) 01:55, 12 February 2012 (UTC)

Parametric types and Generics

Is there any difference between type polymorphism and generics? They both seem to me (with a limited understanding) to be identical, but in different contexts no one ever switches between them (no one ever talks about generics in Haskell for example) so I was just wondering if they were actually synonymous? — Preceding unsigned comment added by SlakaJ (talk • contribs) 02:36, 12 February 2012 (UTC)

The term polymorphism covers a lot of ground. Generics are very much like Haskell's parametric polymorphism, method overloading is vaguely related to Haskell's type classes, and subclass polymorphism has no straightforward equivalent in Haskell. -- BenRG (talk) 02:51, 12 February 2012 (UTC)

A question about audio tone-changing...

Well, I was watching an episode of Naruto Shippuden and I heard the choral piano music at one point (http://www.narutoget.com/watch/666-naruto-shippuden-episode-138-english-subbed/ - music starts at 13:50). Then I watched the episode in Spanish subs on Tu.tv, but I noticed the choral piano music had a different tone (http://tu.tv/videos/naruto-shippuden-138-sub-espanol-3-3_1/ - music starts at 00:35). As I heard it, I thought it might be possible to make music sound in a different tone. I wanted to try out taking a music clip or sound and change the tone to a different tone. Are there software programs or tricks to do that? — Preceding unsigned comment added by Sirdrink13309622 (talk • contribs) 13:57, 12 February 2012 (UTC)

That is possible; it's called pitch shifting. The reason why you hear TV music in a different pitch however, is due to a process called PAL speedup during conversion from a NTSC video source to PAL. Sometimes, pitch shifting is used to counteract this effect, resulting in the music having only a higher tempo, while the pitch is maintained. — Edokter (talk) — 15:14, 12 February 2012 (UTC)

This explains a lot everything... --190.158.184.192 (talk) 17:15, 12 February 2012 (UTC)

Client-side wiki software

Hi,

I'm looking for a client-side-only wiki software which would run on Windows XP. I found TiddlyWiki, but it is a single-user wiki, while I'm looking for a multi-user wiki (I assume there will be only good faith users, so I don't need a real user authentication system, although this could be done through encryption and digital signatures). Also, I prefer avoiding the use of Javascript in a web browser, because I'm not sure which web browser will be available, so there could be compatibility issues with a software like TiddlyWiki.

Thanks.

Apokrif (talk) 18:13, 12 February 2012 (UTC)

XAMPP ¦ Reisio (talk) 22:18, 12 February 2012 (UTC)

Thanks for the hint, but I'm looking for something more lightweight (if I don't find what I need and I end up writing it myself, I would first try in VBS or VBA). Apokrif (talk) 00:49, 13 February 2012 (UTC)

"AirPort"

I use an AppleMac and it's Airport for syncing with my iPad and iPhone via my router. This is a puzzle to my wife, and being non literate in these matters I have difficulty in explaining how "AirPort" works. Any ideas please, I guess 'radio waves', but this does not seem right somehow.--85.211.170.102 (talk) 18:56, 12 February 2012 (UTC)

Airport is just Mac's trademarked term for a WiFi router. So if you have an Airport card, that just means you have an Apple-branded WiFi card. Radio waves is close enough. WiFi is a form of electromagnetic radiation, like radio or microwaves or infrared or visible light. Specifically it uses either 2.4GHz or 5GHz spectrum bands, well within the definition of radio waves. Basically the Airport/Wifi cards in your iPad and iPhone use very complicated means to send information packets to the antennae on your Airport/Wifi router, which then relays them back to the other device for syncing, or something along those lines. The details of how it sends the information are quite technical. --Mr.98 (talk) 21:24, 12 February 2012 (UTC)

Wow! Thanks--85.211.170.102 (talk) 06:32, 13 February 2012 (UTC)

Types of 3d in games

Are there words for different types of 3d in games? I don't mean those new games with 3d effects, but, for example, a differenciation between a cube on a screen, which is shown only from one angle and a cube that can be twisted. The second would be more 'real'. — Preceding unsigned comment added by 83.36.33.29 (talk) 20:05, 12 February 2012 (UTC)

There are many terms, but I don't think they are unique to games, but apply to all 3D visualizations. Some games allow a limited number of "camera angles", too. StuRat (talk) 20:09, 12 February 2012 (UTC)

You're probably thinking about the difference between isometric projection (sometimes called 2.5D or axonometric projection/oblique projection/parallel projection - there's slight differences between them, depending on how technical you want to get) with a non-rotatable camera and perspective projection ("true" 3D rendering) with a fully mobile camera. See also Video game graphics and Isometric graphics in video games and pixel art for more details. -- 140.142.20.101 (talk) 21:11, 12 February 2012 (UTC)

See sprite for the use of 2D images in graphics; it has a lot of discussion about pre-projected 2D images of objects can be used in a 3D context. SimCity 2000 is an example of a game whose graphics were totally isometric and sprite-based. Doom used sprites (with a small number of different view angles) to render various objects, such as the enemy creatures. Paul (Stansifer) 21:28, 12 February 2012 (UTC)

I could be wrong, but I don't think you are talking about the difference between isometric and perspective projection. Your question seems more about "real-time" 3D, as you typically see in Virtual reality and most 1st/3rd person shooters, and high-definition rendering as used in cut-scenes and the CGI movie business. The first is generated on-the-fly, 20-30 frames per second, and uses various tricks to cut down on the amount of detail that needs to be drawn. The user can define the viewer's position and orientation. The second produces a much higher degree of "realism", with complex lighting and reflection calculations, but each frame takes several minutes or even hours to generate, so movement through the scene must be pre-defined. The relevant articles, as linked from Computer-generated imagery would appear to be Interactive visualisation and Computer animation Rojomoke (talk) 14:37, 13 February 2012 (UTC)

Search Engine Behaving Badly in Firefox 10.0.1

My search engine was recently changed to Yahoo by some software (YouTube Downloader) I got from Download.com (the option to refuse was greyed out). Anyway, I changed it back to Google using the about:config thingummijig, but now it's behaving oddly. For example, I type in a word, say, "barley", and it sends me straight to the Wikipedia page. I type in an actor's name, and I get sent immediately to the IMdB. I want Google Search results. I guess something or other is set to 'automatically choose the top search result'. I do not have the independent search bar in the top right, but rather I search directly from the address bar, and have been doing so for several years. This problem has only appeared this evening and it's annoying because I use Google extensively in my work. Can anyone help? KägeTorä - (影虎) (TALK) 22:01, 12 February 2012 (UTC)

What happens when you type in "google.com" and then enter your search term in the Google search box ? StuRat (talk) 02:51, 13 February 2012 (UTC)

That does indeed give me Google, but the ranking of the search terms is different, with mostly Google Books pages at the top. KägeTorä - (影虎) (TALK) 03:34, 13 February 2012 (UTC)

Well, it won't be perfect, but that does suggest that bookmarking the Google search page will give you a way to get to the Google search result list, fairly quickly. StuRat (talk) 03:37, 13 February 2012 (UTC)

What setting did you change in about:config, and what did you change it to? Does it have some mention of "I'm feeling lucky"? Paul (Stansifer) 04:03, 13 February 2012 (UTC)

I changed the 'keyword.url' to: 'http://www.google.com/search?ie=UTF-8&oe=UTF-8&sourceid=navclient&gfns=1&q=' (no quotes), which is the normal default as per MozillaZine Knowledge Base. KägeTorä - (影虎) (TALK) 04:11, 13 February 2012 (UTC)

February 13

PDF question

Hi. (MacOSX/kubuntu; free softare only). I have two PDFs (one texty with a few images, one a light-coloured pattern, which I want to use as a background for the other PDF). How can I "merge" these two PDFs together so the background is 'behind' the texty PDF? Robinh (talk) 00:47, 13 February 2012 (UTC)

1. Separate out the image from the background PDF (e.g. use the Gimp or something to convert it to a PNG or JPEG); 2. use pdftk to use the background image as a "background watermark" to the original PDF. --Mr.98 (talk) 01:06, 13 February 2012 (UTC)

Thanks for this. Currently trying to install pdftk and am in dependency hell. Why do 90% of packages install (configure;make;make install) out of the box, and 10% involve some long complicated insane dependency list that makes the package impossible to install? Is there a macosx binary out there? Robinh (talk) 02:05, 13 February 2012 (UTC)

It looks like there is an installer here: [4] Google turns up some other pages, but they all seem link back to that one. RudolfRed (talk) 03:26, 13 February 2012 (UTC)

I entirely sympathize, but I don't have an answer. It's my biggest pet peeve about open source software on the Mac. Installing from complicated packages, installing from source... huge time sinks with no apparent benefit. There is a Mac installer linked to on the pdftk site, though, which might be easier than making it up through source or a package manager. --Mr.98 (talk) 03:25, 13 February 2012 (UTC)

Ironic that it's writ in Java™ and a pain to install. https://github.com/mxcl/homebrew/issues/6171 :p I'm a little curious how easy it'd be to use Gentoo prefix for this. ¦ Reisio (talk) 14:45, 13 February 2012 (UTC)

(OP) Well, there *was* a binary available, which worked. But its idea of "merge" wasn't what I wanted. I was advised (offline) to use inkscape, which worked perfectly.

Resolved

Robinh (talk) 20:07, 13 February 2012 (UTC)

dynamic url shortener

Hello uhmm I want to create an url shortener (because I'm constantly updating links) where you can modify the redirection page... There is one at ad.fly but that site has a bad reputation.. so do you know sites with that service? 190.158.184.192 (talk) 02:29, 13 February 2012 (UTC)

IT

1. Electronic jobmarketing and placement106.78.175.29 (talk)

2. Electronic option106.78.175.29 (talk)

3. Secure hypertext transfer protocol106.78.175.29 (talk)

4. Electronic fund tranfer106.78.175.29 (talk)

5. Encryption and decryption106.78.175.29 (talk)

6.Authentic Protocol106.78.175.29 (talk)

7.Electronic mail security106.78.175.29 (talk)

8. Difference between B2B And B2C106.78.175.29 (talk)

9. E payment And Esecurity threads106.78.175.29 (talk)

10. Digital Signation106.78.175.29 (talk) —Preceding undated comment added 02:42, 13 February 2012 (UTC).

None of those appear to be questions (except perhaps 8). Don't just list a bunch of topics here, look them up yourself and come back with any questions about them after. StuRat (talk) 02:48, 13 February 2012 (UTC)

Viability of playing video games on a non-gaming PC

I am in possession of a Personal computer which I wish to use for the purpose of gaming - specifically, I am interested in playing the games Deus ex, Super Meat Boy, and Braid. However, my PC is only a standard laptop computer, not specifically designed for gaming. Are any of these games playable on an ordinary PC with no extra gaming-oriented features, or do they all require special graphics/sound cards, etc.?--142.166.223.135 (talk) 02:51, 13 February 2012 (UTC)

No games require special graphics/sound cards specific to them. You have two options: 1) Check the specifications of each game, and see if your PC meets at least the minimum specifications. If it does, then you should be able to run them; or 2) Download the demo versions (Deus Ex here, Braid here, and the demo of Super Meat Boy is available somewhere) of those games and try the games out to see how they work on your machine. Good luck! KägeTorä - (影虎) (TALK) 04:07, 13 February 2012 (UTC)

What good choices of games! If you like SMB and Braid, you'll probably also like VVVVVV. To answer your question, none of those games are particularly demanding to the computer. I think that all three will probably work on integrated graphics card that your laptop is likely to have. Braid is the only one that I'd be worried about. To make a wild guess, any (non-netbook) laptop that was made in the last couple of years (maybe more) should be able to handle it. But I don't know much about graphics hardware. Can you tell us more about your machine? Paul (Stansifer) 13:23, 13 February 2012 (UTC)

Why worried about Braid, a 2D platformer? Comet Tuttle (talk) 16:58, 13 February 2012 (UTC)

Braid is a pretty heavy user of OpenGL for storing graphical elements in the video memory and uses Cg shaders for compositing, blurring, shadows, and lighting. Here they say "please ensure that you are using drivers that enable 3D acceleration". -- Finlay McWalterჷTalk 17:39, 13 February 2012 (UTC)

Even items that appear to be rendered in "2-D" may make heavy use of hardware-accelerated APIs. The on-screen image doesn't always provide any insight into the programmatic way that the pixel values were computed and placed on the screen. Our article, Graphics processing unit, has a great overview: historically, the GPU accelerated matrix transform mathematics that was useful for calculating graphical projection and transforming and mapping textures onto polygons; these were most useful for 3D, but can equally-well be used to render two-dimensional shapes. Modern GPUs do all kinds of extra work - and in the case of a GPGPU paradigm, function as a generic multiprocessor computer, perhaps not even used for graphics-related tasks. The original question was about terminology: is a "gaming" computer any different than a regular computer? No, it is not; it's just a computer that is generically described as "suitably powerful" for most common games. You should check specs for each software package to ensure compatibility.

The ultimate point is, if a game's vendor says it requires certain hardware, you should probably believe the vendor, even if you don't understand the logic behind the requirement. Nimur (talk) 18:01, 13 February 2012 (UTC)

For example, the opening scene of Braid looks to have about 8 layers of objects, each scrolling at different rates and containing multiple independent animating objects, that all have to be smoothly composited with alpha blending over the full screen at 60fps. This post has someone complaining it doesn't work nicely on his EEEPC. The steam page for Braid says it needs DirectX 9 with pixel-shader 2.0 -- Finlay McWalterჷTalk 17:54, 13 February 2012 (UTC)

With regard to what Paul Stansifer said: I'm not especially computer savvy, so I'm afraid I can't tell you much about my machine, but it's a Sony Vaio laptop with 6 GB of system memory, an Intel i5 core, a CPU clock frequency of 2.30 GHz, and an Nvidia Geforce something-or-other.--142.166.223.135 (talk) 01:56, 14 February 2012 (UTC)

That will breeze it with those games, easily. Mine's an HP dv6, with 4GB RAM, Intel i5 core, 2.27GHz, and NVidia GForce 105M, and I can play a lot of higher end games on mine with no problem. You'll be fine. Have fun! KägeTorä - (影虎) (TALK) 02:20, 14 February 2012 (UTC)

Firefox as daemon

I use ChatZilla, and may also need the Firefox version of Zotero so I can use LyZ. However, I rarely use Firefox as a browser. Is there any way to install it as a lightweight daemon, so that it can run extensions with no browser windows open? NeonMerlin 02:55, 13 February 2012 (UTC)

XULRunner 82.45.62.107 (talk) 10:10, 13 February 2012 (UTC)

Windows 7 screen saver deactivation

Is there a way to make Windows 7 not ask for Ctrl-Alt-Del every time that the screen saver is deactivated? I want to just move my mouse or hit a key, get the login prompt, and start typing my password. I don't want to have to do the three finger salute every time. Thanks, Dismas|^(talk) 03:44, 13 February 2012 (UTC)

In the control panel where you set your choice of screen saver, is there not a tick box saying "On resume, password protect". There is on Windows XP (and maybe Vista too). (edit) See this image for an example of what I mean. Astronaut (talk) 10:51, 13 February 2012 (UTC)

(edit conflict)I think you misunderstood. I don't want to disable the password. The way it works in 7 is that to deactivate the screen saver, you have to 1) hit a key or move the mouse, 2) hit Ctrl-Alt-Del, 3) type in your password. I just want to take out the extra step of having to hit Ctrl-Alt-Del in order to get to the screen to put in my password. Dismas|^(talk) 10:56, 13 February 2012 (UTC)

See this Microsoft article: How to enable or disable the CTRL+ALT+DELETE sequence for logging on to Windows XP, to Windows Vista, and to Windows 7. I don't know if this will apply to the screesaver as well though. — Edokter (talk) — 12:02, 13 February 2012 (UTC)

Certainly on XP and Vista, if you remove the tick from "On resume, password protect", moving the mouse stops the screen saver and returns to your desktop without having to type CTRL+ALT+DEL or enter your password. Sorry, reread it again and you are right, I'm answering a different question from the one you asked. Astronaut (talk) 12:04, 13 February 2012 (UTC)

Yes, but the poster does not want to disable the password, just the ctrl-alt-del part. — Edokter (talk) — 12:06, 13 February 2012 (UTC)

Ping Response

What is the opposite of a 'ping response'? Is it 'ping transmission'? 'Ping emission'? Something else? This is actually a language question but I thought I may get a better answer here. Just in case, the Japanese is 'PING発出'. KägeTorä - (影虎) (TALK) 14:58, 13 February 2012 (UTC)

Ping is a program; ICMP ECHO is the network packet type it uses. The transmission is an "echo request" and the reply is an "echo reply". ICMP ECHO is also used by traceroute and similar network tools. See Ping#Message format-- Finlay McWalterჷTalk 15:23, 13 February 2012 (UTC)

Yes. This is for a translation of a .ppt slide, though. I would rather keep to the original format as close as possible. Would 'ping transmission' sound wrong? KägeTorä - (影虎) (TALK) 15:53, 13 February 2012 (UTC)

I'd write "ping request", which gets a fair number of Bing results. "Ping transmission" gets two orders of magnitude fewer results. FWIW --LarryMac | Talk 16:22, 13 February 2012 (UTC)

I would write "ICMP packet", which is the technically correct term for "the data that is transmitted when you run the ping program." If I were being sensitive about terminology, I would also write, "a user started the ping program,"; "ping initiated a transmission of an ICMP packet" and "ping received an ICMP echo reply message." If you want some more guidelines on the pedantic details of terminology, the canonical source is RFC 792, from the Internet Engineering Task Force, which is the official specification of the format and terminology. I know that in practice, even I simply say "ping," or "the server had a 20 ms ping," which is very loosely conflating the program, the transmitted data, and the action of receiving a reply, into one word with ambiguous meaning. Nimur (talk) 18:07, 13 February 2012 (UTC)

You didn't give us the sentence or context but I would rarely or never use the term "ping transmission"; I would probably call it a "ping". What's the sentence? Comet Tuttle (talk) 16:56, 13 February 2012 (UTC)

That is the sentence, unfortunately. It's just two words, in a diagram. The opposite end of the diagram has 'ping response/reply', again, just two words. I was thinking of 'ping request' as LarryMac suggests, but the Japanese doesn't say that here, and it does say 'ping request' elsewhere in the set of documents I am translating. KägeTorä - (影虎) (TALK) 19:07, 13 February 2012 (UTC)

In fact, in some cases, ping is used to refer to the transmission, and pong for the reply, List of Internet Relay Chat commands#PONG, [5], [6] Nil Einne (talk) 18:39, 13 February 2012 (UTC)

Convert text to key presses

I am trying to enter a whole load of information (about a page of A4) into a web text form. I already have the text saved in a text file, but the site has disabled copy/paste. Since I don't really want to type it all out again (which might introduce errors), I would like to find some way that I can convert the text into key presses. My idea is that, if I copied the word 'Hello', I could then put the cursor in the text form, and fool it into thinking I was pressing 'shift+h-e-l-l-o', thus reproducing the word. Is this possible? Is there some (free) software to do it? I am using Ubuntu 11.10. - Cucumber Mike (talk) 15:54, 13 February 2012 (UTC)

You can probably just disable JavaScript, paste it in as you please, then re-enable JavaScript and submit it. If it's not a particularly badly coded form, you can probably disable JavaScript and not even be bothered re-enabling it before submission. ¦ Reisio (talk) 16:16, 13 February 2012 (UTC)

It's possible old bean that you can't right-click and paste the verbiage, but the old keyboard shortcut (CTRL-V) might still bally well work - worth a shot in my book! Quintessential British Gentleman (talk) 19:14, 13 February 2012 (UTC)

Already tried that dear boy. Ruddy thing put the kybosh on it. Jolly poor show, eh what? - Cucumber Mike (talk) 22:08, 13 February 2012 (UTC)

If the above doesn't work, you can use this program (which I almost entirely ripped off someone else), which uses the Xtest interface to type key events into another window. It works for normal characters, but not for non-ascii ones. You may need to install the python-xlib package from the Ubuntu repository. -- Finlay McWalterჷTalk 21:14, 13 February 2012 (UTC)

This looks perfect thank you! Now the problem is my complete lack of Ubuntu savvy. Can you explain how to use this, as if you were talking to someone partially brain-dead? I mean, I assume I have to do something in the terminal, and the file says at the top "# type file into the current X window", but I'm lost already. What's an X window when it's at home? - Cucumber Mike (talk) 22:08, 13 February 2012 (UTC)

I believe "X window" just means "window". StuRat (talk) 23:19, 13 February 2012 (UTC)

Yeah :) That line is just an explanation of what the program does, it's not an instruction for use. Some instructions for use, then:

• Save the file (it should be called sendkeys.py) to your computer
• Make sendkeys.py executable (right-click on it, properties, permissions, make sure "allow executing file as program" is checked)
• In synaptic (urgh, or probably Ubuntu Software Centre) install the package python-xlib (if it's not installed already)
• With a plain text editor like gedit (not a word processor like LibreOffice Write) create the file foo.txt in the same directory as sendkeys.py, and save in there all the text you want typed in
• Open a terminal and cd to the folder where sendkeys.py is stored
• Type sleep 5 ; ./sendkeys.py, press return, and quickly click on the browser edit box you want stuff typed into
• After 5 seconds it'll type stuff for you

The program only knows about basic characters, so stuff like currency symbols (even £) and non-ascii characters like ø and ü will cause it to fail - so experiment with simple stuff first. I'm off to bed. -- Finlay McWalterჷTalk 23:51, 13 February 2012 (UTC)

Regex help requested

I'm trying to work with AWB's find and replace tool. I need to separate two parameter in an infobox into four parameters, but I'm having difficulty.

I need to convert:

|birth_date={{birthdate|1900|01|01}}<br>[[Omaha, Nebraska]]
|death_date={{deathdate and age|2000|01|01}}<br>[[Lincoln, Nebraska]]

To:

|birth_date={{birthdate|1900|01|01}}
|birth_place=[[Omaha, Nebraska]]
|death_date={{deathdate and age|2000|01|01}}
|death_place=[[Lincoln, Nebraska]]

I have two rules (one for birth, one for death), and this is what I've got:

Find (for both birth and death parameters):

\}\}<\/?br.*>\[\[

Replace with (same with death_place):

}}
|birth_place=[[

The problem is, I cannot seem to get the birth find-and-replace to only replace the birth parameters and not the death parameters. Any help would be appreciated. Eagles 24/7 (C) 22:26, 13 February 2012 (UTC)

It'd be helpful if you post what happens when you run it... but that might not be necessary as I suspect I know your problem. If you're matching multiple lines (which has always been tricky in AWB for me) then the .*>\[\[ portion of your regex is greedy so it's grabbing everything between the first <br> and the last [[.

Try using .*? instead and see if that works. Shadowjams (talk) 00:24, 14 February 2012 (UTC)

Tried it, same result. I get this when I run it:

|birth_date={{birthdate|1900|01|01}}
|birth_place=[[Omaha, Nebraska]]
|death_date={{deathdate and age|2000|01|01}}
|birth_place=[[Lincoln, Nebraska]]

"Regular expression" is ticked for both rules, if that helps. Eagles 24/7 (C) 00:28, 14 February 2012 (UTC)

Use the following regex for finding the birth date.:

\{\{birthdate([0-9\|]+)\}\}<br>\[\[

The 'replace' field should be:

{{birthdate$1}}
|birth_place=[[

→Στc. 01:01, 14 February 2012 (UTC)

Didn't work, doesn't seem the "find" was correct. Eagles 24/7 (C) 01:15, 14 February 2012 (UTC)

I should have clarified: this also include {{birthdate and age}} templates as well. Otherwise, the regex works. Eagles 24/7 (C) 03:54, 14 February 2012 (UTC)

February 14

Computer clock drift

Why is it that computer clocks drift so quickly? Why aren't there (or are there?) quartz clocks to keep, or synchronize computer times? I notice drift on the order of 3 seconds per 24 hours on one of my machines... which seems extreme. This isn't a practical issue because I just synchronize to a time server, but why is it so dramatic in the first place? Shadowjams (talk) 00:20, 14 February 2012 (UTC)

Because the NMOS RTC is cheap crap and the CPU, which clocked very fast, isn't intended as an accurate timekeeper and these days is downright narcoleptic. Last time I had a Sun workstation (which was a decade ago) it kept time, even when off for weeks, like a Swiss watch - because its battery-operated TOD clock wasn't cheap crap. The very few PC users that really need accurate time (e.g. for stock trading or astronomy) install accurate clock cards (or radio-time cards). -- Finlay McWalterჷTalk 00:30, 14 February 2012 (UTC)

For a (to my mind rather fascinating) discussion about the problems of fixing clock drift with a naive NTP sync, and the more sophisticated steps that need to be taken to ease the adjustment in slowly, see this documentation about the Dovecot mail server. -- Finlay McWalterჷTalk 00:46, 14 February 2012 (UTC)

And I'd say the reason why so many PCs come with such crap clocks is because the clock accuracy isn't listed along with the essential stats (RAM, HD size, MHz, etc.). If it was, people would complain that they don't want to spend so much for a computer with such an inaccurate clock. StuRat (talk) 05:10, 14 February 2012 (UTC)

Can I somehow "repartition" and burn a Blu-ray disk (BD-RE) to behave like two or more DVDs?

Why I need this: When borrowing a series of films on DVD at my local library (for instance the eight Harry Potter films), I would like to view them in the correct order but there is a 7 day time limit on each loan, and not all films are available at the same time.
Thus I would like to make a temporary copy, on BD-RE, util I have them all (and can see them chronologically).
My question: How can I copy two or more DVDs onto a BD-RE, including everything from the DVD (menues, extra material, various subtitle languages etc.) in such a way that I in the end may view them by VLC media player almost as if I still had each single DVD at hand ?
(I have a limited budget and therefore will have to rely on free software or standard features in Windows7 or maybe Ubuntu).
Is it possible?
--Seren-dipper (talk) 00:37, 14 February 2012 (UTC)

You're looking for a program like DVDFab, which can do a lot of things like what you're asking (I think it has a free trial version). However, it seems like you're going to more work than necessary. If you're just trying to be able to play back DVDs later, from your computer, you don't need to put them on a Blu-ray disc - you can put them your hard drive using a DVD decryption software (such as the free version of DVDFab, or something like DVD Decrypter, which is free, but no longer supported). If you just want to store the movie data on a Blu-ray disc so it doesn't take up space on your hard drive, you would decrypt the DVD (probably saving to your hard drive), and then use your Blu-ray burner to just burn the files to the Blu-ray disc, and delete them from your hard drive. If you want to be able to put your Blu-ray discs in a standard Blu-ray player (i.e. not one attached to your computer with VLC on it) and have them play, you'll need to be a bit more careful about it (using a program like DVDFab that's designed to do it would probably be best), and I'm not sure that you're going to be able to put multiple DVDs on one disc (but I might be wrong).

We don't give legal advice here, but in some jurisdictions, it may be illegal to circumvent technical copy restrictions on electronic media, including the Content Scramble System that is almost certainly used on the DVD's you are interested in. Buddy431 (talk) 04:23, 14 February 2012 (UTC)

Exploit:JS/Blacole.BV

If my antivirus says it was successful at removing it, should I believe it or can this virus find a way to hide itself into the system that would require manual removal? 70.52.77.66 (talk) 05:18, 14 February 2012 (UTC)