Wikipedia:Reference desk/Archives/Computing/2010 June 11

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June 11[edit]

problem with windows media player 11[edit]

hey guys im having a problem with windows media player 11 i have vista home premium and wmp11 worked fine until recently now when i play some songs it wont play them and says "your computer is low on memory. quit other programs, and then try again." however they work fine on itunes. also my laptop just got back recently from acer pretty well brand new so i have no idea why this problem is happening.Alive99 (talk) 00:02, 11 June 2010 (UTC)

Sounds obvious it is running out of memory. A few things come to mind:
  1. You say you got it back from Acer, so presumably that was a repair. Maybe they didn't re-seat the memory correctly, so the laptop now only has half the memory it should. Or maybe some of the memory is faulty.
  2. Maybe you have not run out of real memory, but have run out of virtual memory. This can happen if your disk is very full.
  3. Maybe you are running some resource hog of a program. Games and video editing make high demands on a PC's resources. But maybe it is some program you cannot see easily, that starts automatically ... perhaps malware.
Astronaut (talk) 01:09, 11 June 2010 (UTC)
First off forgive me if you have to have some sort of endorsement to post on here, just figured I'd chip in (sorry if I'm not allowed to!)
It seems way too presumptuous to put this down to a bad reseat or malware -- with no specs on the laptop, it is quite possible it is a low-end model (or even a netbook, like the Aspire One and the like). As such, the main questions that need to be answered before a solution can be found are:
  1. How much RAM does the laptop have?
  2. When getting this error, what are the stats listed in the 'physical memory' section of task manager, on the performance tab?
  3. What sort of media are you trying to play? (For example, a video, or audio?)
Again, apologies if I am not eligible to post here, just thought I'd throw in my two cents. Findstr (talk) 02:47, 13 June 2010 (UTC)

Running out of space on a RAID[edit]

I have a computer running Mac OS X 10.5. It has a 500GB RAID with only 11GB empty. The system drive is 250GB with only 16GB empty. Could these items be a reason for a system wide slow down and reduction in performance? Dismas|(talk) 01:35, 11 June 2010 (UTC)

I'm skeptical. That's a lot of space compared to the amount of RAM in your PC. First thing I'd look for is any new software you've installed or updated. If that's not the issue, have you tried defragging? Comet Tuttle (talk) 04:07, 11 June 2010 (UTC)
While I'm a master at letting my drives get way too full and 11GB and 16GB isn't bad compared to what I often end up with, you should be aware that most modern filesystems and OSes work best (in avoiding fragmentation and defragmenting etc) when you have a decent amount of freespace. At least 5% would be the minimum recommendation but some may recommend up to 10% or more [1]. In FreeBSD and I think Linux 5% is normally automatically reserved (with the root user you can usually go over the limit so you can see up to ~105% usage if you run df) mostly for this reason I believe. I'm not sure if Mac OS X does this, if it doesn't you may want to increase the freespace particularly for the 500GB drive. Of course if you've defragmented the 500GB drive resonably well and the content doesn't change then this isn't much of an issue (and of course generally it depends a lot on how much the content does change and other factors). You should also be aware that most hard drives may be ~half the speed of the beginning, at the end of the drive (and they also have a high seek time so you ideally don't want to be jumping around the drive too much). However unless you're doing a lot of disk intensive work all the time, I too am doubtful this would cause a system wide slowdown. Nil Einne (talk) 11:04, 12 June 2010 (UTC)

Comcast Cable Internet Speeds[edit]

I've been considering upgrading from the Comcast performance package (12mbs down) to Blast!(16mbs). How big of an impact will this have on the time it takes me to actually download large files in practice; in short, will I notice an appreciable difference is speed on a regular basis? The cost to upgrade is an extra $10 per month, just want to make sure this is worth it. Thank you:) 66.202.66.78 (talk) 05:39, 11 June 2010 (UTC)

Well, even in theory you're only adding 4 mbs, under very ideal conditions—namely, that the server you are downloading from is capable of giving it to you at a max speed anyhow, and that your line conditions are such that you are really getting all of that data at the top speed anyhow. For a situation where the former condition is definitely met (like torrenting a file with a huge number of seeders, which seems to be able to max-out one's down bandwidth pretty well in my experience), a 10GB file would download in about 12 114 minutes at 12mbs, and in about 9.75 85 minutes at 16mbs (there is some rounding here, but the calculation is just converting the GB into bits, and then the megabits into bits, and dividing, and then converting those seconds into minutes—all pretty easy with Google's unit conversion feature)—so a total difference of half an hour in such a situation. That's under ideal conditions of them being maxed out all the way. Is that worth an extra $10 a month, or $120 a year? Personally I probably suspect not, but that's a value judgment, and depends heavily on your own usage habits (for me, as someone who only downloads large files but rarely, it wouldn't be worth it). But perhaps there are additional benefits of a slightly higher down rate that I am not thinking of. --Mr.98 (talk) 16:04, 11 June 2010 (UTC)
Your math is off:
  10,000,000,000 bytes
x                     8 bits per byte
  80,000,000,000 bits
  80,000,000,000 bits
÷      16,000,000 bits per second
                5,000 seconds
And 5,000 seconds equals 83 minutes. Do the same math for 10 mbps, and you get 133 minutes. So, you save 40 minutes when downloading a 10 GB file. I save an additional 30 minutes at 24 mbps.
I have the 24 mbps Ultra package from Comcast. Web pages don't load any faster, but streaming video and downloading large files are much faster. It takes about three seconds for the connection to speed up completely. Since most simple web pages finish loading in under that time, it only impacts streaming video (e.g., Netflix, YouTube HD) and downloading large files from fast servers (e.g., updates from Microsoft, trial software, torrents, Rapidshare, etc.).--Best Dog Ever (talk) 17:32, 11 June 2010 (UTC)
(Assuming we are using "real" GB and not harddrive manufacturer GBs, 10GB is not equal to 10,000,000 bytes; its 10,737,418,240 bytes. 16Mb is 16,777,216 bits. But you're right, I missed out converting GB into bits, which is the key part.) --Mr.98 (talk) 19:01, 11 June 2010 (UTC)
No, a gigabyte is 10,000,000,000 bytes. A gibibyte is 1,073,741,824 bytes. Findstr (talk) 17:34, 13 June 2010 (UTC)
No a gigabyte is 1,000,000,000 bytes or sometimes defind (inacuratly) as 1,073,741,824 bytes never 10,000,000,000 bytes.Gr8xoz (talk) 00:27, 14 June 2010 (UTC)

Some Windows installation related questions[edit]

I just installed and run Windows 7. But this version of Windows give me lotta confusions.

  1. Is a full format (not a quick one) harmful to the HDD? I have heard many of my friends say that when full formatted too many times, a partition can be corrupted. I'm not sure 'bout it but I have broke a few floppy disks in the past due to formatting to get rid of some viruses.
  2. When installed, it ask me to choose whether I like to install x86 or x64 version of Windows 7. My laptop is an crappy one with a Celeron @ 560 2.13 Ghz and 768 MB of RAM. I know that my CPU is 32 bit so I choose to install x86. I used to think x64 version only works with a 64 bit CPU, but a few hours ago I tried to install a x64, waiting for an error message, but unbelievable, it works! I'm running IE8 64 bit now. So, which version should I use?
  3. Do 64 bit programs run faster on a x64 OS than 32 bit ones running on a x86 OS?
  4. I still want to run an additional OS on my computer (Windows XP) to play games. This windows takes lotta RAM, which make most of my favorite games unplayable. But I surf the web and find many complaining that their Windows 7 no longer works after they install XP. To get both of them work, I must install XP first, then 7, right? (on different partitions of course)

Any help would be very appreciated. -- Livy the pixie (talk) 11:33, 11 June 2010 (UTC)

1. No.
2. The 560 is a Merom core, which means it features ia64. But I'd still run the 32 bit version; I don't think you'll see any advantage in 64.
3. It depends on the program. 64 bit programs are a bit less cache-efficient and a bit more memory-hungry (big ints, big pointers). A few programs actively benefit from the wide words, but I doubt very much you'll use any of them. If you did lots of media encoding, and you knew the codecs you used had 64 bit versions, then maybe that'd be a consideration.
4. Windows 7's compatibility is pretty impressive, and very few things that work on XP won't on 7. In the unlikely event that you do find something that just plain won't, install XP in a virtual machine inside windows 7. Dual-boot is a bad idea.
-- Finlay McWalterTalk 11:47, 11 June 2010 (UTC)
I'm not convinced that running XP in a virtual machine on a computer with only 768 MB of RAM is a good idea, especially since the OP is concerned about gaming performance. (PS: IA-64 is Itanium; the 64-bit successor to x86 is variously called x86-64, x64, amd64, EM64T, ...) -- Coneslayer (talk) 11:52, 11 June 2010 (UTC)
The amount of RAM you have is below the minimum requirement for Windows7 (see Windows 7#Hardware requirements). Even if you updated that, your CPU is pretty ancient, and is near the bottom of the acceptable range for Windows 7 (if you must, run Microsoft's Upgrade Advisor on the laptop). I wouldn't install Windows 7 on this machine. -- Finlay McWalterTalk 11:54, 11 June 2010 (UTC)

I know Microsoft has offered something call XP mode, but it require an additional 1 GB of RAM and I'm running out of it. I'm waitin for a new laptop next year so I don't want to upgrade my PC at the moment. To dual boot, I have to install the old version of Windows first, then the newer one after, right? I remember seeing it somewhere on Microsoft homepage, but this article is for Windows Vista. I'm not sure it is still correct in Windows 7 or not. -- 123.16.22.244 (talk) 11:57, 11 June 2010 (UTC)

XP mode just means it comes with a VM included. Coneslayer is right, you don't have enough memory for it. But you don't have enough memory for Windows 7 anyway. -- Finlay McWalterTalk 11:59, 11 June 2010 (UTC)
... (after edit conflicts) and, to add to Finlay's answer to 1, formatting any disk is just the same as writing to it except that a low-level format re-writes the sector markers in each track, thus erasing all data. If you format a whole hard drive, this will delete any partitions, though some formatting software will protect you from this possible error. Dbfirs 12:04, 11 June 2010 (UTC)

With 768 MB of RAM I can still run some basic programs in Windows 7, such as IE, jetAudio, NetBean, Visual C#. I have install Windows 7 for 2 weeks w/o any problem. But I need XP for gaming. I install Windows 7 to experiece some new features only. Um, what must I do to dual boot now? -- 123.16.22.244 (talk) 12:05, 11 June 2010 (UTC)

I don't have any personal experience dual-booting them, but here's a guide to dual-booting Windows 7 with either XP or Vista. It assumes you start with XP installed; I don't know if that's the only way to do it, but I would expect most guides will make that assumption, since people generally start with the older OS installed and add the newer Windows 7. -- Coneslayer (talk) 12:46, 11 June 2010 (UTC)
You can do it with Windows 7 or Vista first (I've done it before) although you'll usually have to fix the bootloader since Windows XP doesn't understand the Windows 7/Vista bootloader. Nil Einne (talk) 10:54, 12 June 2010 (UTC)

Ubuntu + Vista DualBoot[edit]

I recently had to reinstall Windows Vista. I suspect it had something to do with Vista believing my disk was corrupt or whatever after I put Ubuntu on as a dual-boot (original question + answers here). Anyway, Vista is reinstalled and works fine, only now I am unable to get into Ubuntu, as the menu does not appear to invite me to choose an operating system to boot into. What should I do now? Also, how can I prevent my previous problem from happening again? TIA! --KägeTorä - (影虎) (TALK) 15:26, 11 June 2010 (UTC)

You need to reinstall grub. Windows normally erases the grub loader when it installs. Here's one way to do it. -- kainaw 16:46, 11 June 2010 (UTC)
Cheers. I actually found that page before you answered, and have come into Ubuntu (using the LiveCD) to do just that, but all I'm getting is 'sudo: grub: command not found' after typing 'sudo grub' in Terminal. A Google search of this gives me some relevant pages, but mostly they are fairly old forum posts and are only half-answered. I'm totally lost. --KägeTorä - (影虎) (TALK) 17:14, 11 June 2010 (UTC)
You may need to say sudo /usr/sbin/grub explicitly. -- Finlay McWalterTalk 17:18, 11 June 2010 (UTC)
Right, well, in the end, I actually did what it says on this page and it seems to be OK. I haven't gone back into Vista yet, so I don't know what's going to happen, but anyway, for future reference I'm posting the answer here. Cheers. --KägeTorä - (影虎) (TALK) 17:33, 11 June 2010 (UTC)
Another answer, my friend, is not blowing in the wind, but rather attached to your older question here: Wikipedia:Reference_desk/Archives/Computing/2010_June_5#Win_Vista_Not_Booting. And I know that because I was the one to attach that answer to your question. ;-) -- 109.193.27.65 (talk) 17:40, 11 June 2010 (UTC)

sql server 2005 se[edit]

Hi! If i try to set to single user a db via gui it works, if try via code it doesn't; but the profiler traces the same statement in both cases! Thank you in advance --217.194.34.103 (talk) 16:49, 11 June 2010 (UTC)

Most "durable" file compression format[edit]

What file compression format(s) provide the best "durability" — that is, the most error correction or ability to uncompress contents even if the media is degraded or the archive is missing some bits. I was curious if newer formats like XAR or 7z offer any benefits in this regard compared to "old school" RAR, ZIP, TAR.GZ, TAR.BZ2. --70.167.58.6 (talk) 18:41, 11 June 2010 (UTC)

Those formats that use solid compression are less durable (that includes 7zip and RAR, and in practice those that compress a TAR), as they don't reset the compression dictionary when processing each new file. So if one file's worth of data is damaged, subsequent files are also unrecoverable. With those that do reset the dictionary for each file (ZIP), only the damaged file itself should be entirely unrecoverable (depending on the nature of the damage, naturally). I can find very little information about how XAR works in this regard. -- Finlay McWalterTalk 19:02, 11 June 2010 (UTC)
Solid archiving is optional in the 7-zip and Rar formats. The fact that Zip doesn't support solid archiving can hardly be called a point in its favor. XAR (which I hadn't heard of) apparently has no support for solid archiving, even though the "X" is supposed to stand for "extensible". I can't see any reason to use it. They're not even marketing it for backup usage, but for things like packaging systems; but solid archiving seems to me rather important in a packaging system, where all files are normally unpacked at once and compression ratio matters. -- BenRG (talk) 00:02, 12 June 2010 (UTC)

RAR has recovery records which you can specify a percentage of, so that if some of the archive is damaged it could be repaired from the recovery record. This of course increases the file size though 82.43.89.11 (talk) 20:36, 11 June 2010 (UTC)

Or you could use any format and add some PAR2 files. -- BenRG (talk) 00:02, 12 June 2010 (UTC)
Or ICC ECC (albeit only Windows or perhaps Wine and not unfortunately open source or openly documented) Nil Einne (talk) 10:29, 12 June 2010 (UTC)

Real-time post-processing audio from speakers[edit]

Hi all,

Does anyone know of any software that can do some form of real-time post-processing of the audio that comes from line out (i.e. to your speakers/headphones), such as audio filtering? A bit like Volume Control but more high-tech, capable of doing more complicated things like filtering out certain frequencies. Not interested in recording the sound - more like modify it on-the-fly and send this output to the speakers.

Sound originally aimed for speakers -> Filtering program -> Filtered sound to speakers

Thanks in advance, x42bn6 Talk Mess 19:40, 11 June 2010 (UTC)

That's an interesting question. Doing this should be possible using the MST framework that Vista and Windows 7 have (I'm assuming you're on Windows) - but I can't find any cases where someone has written a patch-board app that actually does. There are however lots of filter packages available that use Steinberg's Virtual Studio Technology (VST) technology. So you might like to experiment with a VST-hosting application, like AudioMulch or VSThost, the descriptions for which suggest they should be capable of what you want (although it's monumental overkill, really). I confess I haven't tried this in practice. -- Finlay McWalterTalk 20:22, 11 June 2010 (UTC)
I'm somewhat confused what you mean by 'sound originally aimed for speakers' nor how the line out comes in to this. Are you planning to take audio from the line out of one sound card, put it into the line in and then output it through another sound card (or the same sound card if it supports multiple outputs), this seems unnecessary to me just do it before it get's goes to the line out. There's also probably no need to try and hack some filter to capture the audio output if this is what you planned to do.
If you just want to modify any sound your soundcard puts out, the software and/or drivers provided by your manufacturer you usually get a variety of effects including potentially an equaliser you can adjust. Fancy sound cards like expensive Creative ones would usually provide more options although Creative software often leaves a lot to be desired. The real X-fis for example have an audio creation mode although it's not something I've ever used myself. You also can do EAX effects. Regardless of card, in Windows Vista and 7 you may also have access to these via a properties settings for the output (speakers or whatever between levels and advanced) but may also want to look for any mixer your soundcard or chip software/drivers provides. For the cheaper Creative sound cards you can also driver the kX drivers [2].
If you want more advanced then that, you may be able to use ASIO in some way if your sound card supports that output but I'm not that sure if you can do it to any output or only output from certain programs.
Either way, probably better then taking the sound from the line out to the line in or trying to capture the sound via some hacked method or something I suspect.
P.S. You may be able to use VST plugin or DirectX plugins but I'm not that sure if this is how they work, I thought you use specific software which connects/uses these rather then it working with all audio output (e.g. a game as a random example). But it's not something I've really looked in to. I am presuming you at least want to be able to modify all audio output not be forced to use specific programs since otherwise there would seem to be a need to capture all the audio as you appear to be trying to do,
Nil Einne (talk) 10:41, 12 June 2010 (UTC)
Let me guess, this is to filter out the Vuvuzela sounds from the soccer transmissions on TV? -- 109.193.27.65 (talk) 21:53, 13 June 2010 (UTC)
You said it, not me.  ;) Nah, I've seen software out there that comes with some sound cards that allows you to mess around with various things with your speakers like the treble and bass levels, but unfortunately mine doesn't. Might be a little fun to write my own even. Thanks all for the links. x42bn6 Talk Mess 01:39, 14 June 2010 (UTC)
<squeeze>I suggested the TV use because http://de.wikipedia.org/wiki/wp:au is currently discussing the same problem. ;-) </squeeze> -- 109.193.27.65 (talk) 10:44, 14 June 2010 (UTC)
So you have you tried installing the software and drivers for your sound card (or chipset)? Be aware the ones Microsoft provides are usually less full featured. You'll also likely want the latest drivers. If you're using a chipset on your motherboard the chipset maker is usually better then the motherboard maker. Nil Einne (talk) 04:47, 14 June 2010 (UTC)