Super video graphics array

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Super Video Graphics Array or Ultra Video Graphics Array,[1] almost always abbreviated to Super VGA, Ultra VGA or just SVGA or UVGA is a broad term that covers a wide range of computer display standards.[2]

SVGA (4:3) compared with the other display standards.
15-pin D-sub port

Originally, it was an extension to the VGA standard first released by IBM in 1987. Unlike VGA—a purely IBM-defined standard—Super VGA was never formally defined. The closest to an "official" definition was in the VBE extensions defined by the Video Electronics Standards Association (VESA), an open consortium set up to promote interoperability and define standards. In this document, there was simply a footnote stating that "The term 'Super VGA' is used in this document for a graphics display controller implementing any superset of the standard IBM VGA display adapter."[3] When used as a resolution specification, in contrast to VGA or XGA for example, the term SVGA normally refers to a resolution of 800x600 pixels.

Though Super VGA cards appeared in the same year as VGA (1987),[citation needed] it wasn't until 1989 that a standard for programming Super VGA modes was defined by VESA. In that first version, it defined support for (but did not require) a maximum resolution of 800x600 4-bit pixels. Each pixel could therefore be any of 16 different colours. It was quickly extended to 1024x768 8-bit pixels, and well beyond that in the following years.[citation needed]

Although the number of colours is defined in the VBE specification, this is irrelevant when referring to Super VGA monitors as (in contrast to the old CGA and EGA standards) the interface between the video card and the VGA or Super VGA monitor uses simple analog voltages to indicate the desired colour. In consequence, so far as the monitor is concerned, there is no theoretical limit to the number of different colours that can be displayed. Note that this applies to any VGA or Super VGA monitor.

While the output of a VGA or Super VGA video card is analog, the internal calculations the card performs in order to arrive at these output voltages are entirely digital. To increase the number of colours a Super VGA display system can reproduce, no change at all is needed for the monitor, but the video card needs to handle much larger numbers and may well need to be redesigned from scratch. Even so, the leading graphics chip vendors were producing parts for high-colour video cards within just a few months of Super VGA's introduction.

On paper, the original Super VGA was to be succeeded by Super XGA[citation needed], but in practice the industry soon abandoned the attempt to provide a unique name for each higher display standard, and almost all display systems made between the late 1990s and the early 2000s are classed as Super VGA.

Monitor manufacturers sometimes advertise their products as XGA or Super XGA. In practice this means little, since all Super VGA monitors manufactured since the later 1990s have been capable of at least XGA and usually considerably higher performance.

SVGA uses a VGA connector, the same DE-15 (a.k.a. HD-15) as the original standard.

See also Digital Visual Interface which is a common non-analog cable for SVGA and other resolutions.

First manufacturers[edit]

Some of the early SuperVGA manufacturers (in parentheses, some of their models, where available) were:

Comparison chart[edit]

x
(width)
y
(height)
Mega-
pixels
Aspect
ratio
Percentage of difference in pixels Typical
sizes
Non-wide
version
Note
Name WXGA WXGA+ WSXGA+ WUXGA WQHD WQXGA
WXGA 1280 800 1.024 1.6 −21% −42% −56% −72% −75% 15"–19" XGA
WSXGA / WXGA+ 1440 900 1.296 1.6 +27% −27% −44% −65% −68% 15"–19" XGA+
WSXGA+ 1680 1050 1.764 1.6 +72% +36% −23% −52% −57% 20"–22" SXGA+
WUXGA 1920 1200 2.304 1.6 +125% +78% +31% −38% −44% 23"–28" UXGA Displays 1920x1080 video with slight letterbox
WQHD 2560 1440 3.686 1.778 +260% +184% +109% +60% −10% 27"
WQXGA 2560 1600 4.096 1.6 +300% +216% +132% +78% +11% 30"+ QXGA Complements portrait UXGA

References[edit]

  1. ^ Ultra Video Graphics Array (UVGA)
  2. ^ Vipul Verma. "Same monitor yet better viewing". www.tribuneindia.com. Retrieved 2008-03-26. 
  3. ^ Video Electronics Standards Association (1994), VESA BIOS EXTENSION (VBE) Core Functions Standard 
  4. ^ a b Unknown ATI 8-bit videocard, Google Groups 
  5. ^ Need info on old Video Seven VGA card, Google Groups 
  6. ^ http://pdos.csail.mit.edu/6.828/2008/readings/hardware/vgadoc/ADAPTERS.TXT
  7. ^ "WESTERN DIGITAL's PARADISE HAS VGA-COMPATIBLE BOARDS", Computer Business Review, October 5, 1987 
  8. ^ VGA, or what to do with my tax return!, Google Groups 
  9. ^ VGA monitor and adapter choices, Google Groups 
  10. ^ IBM's EGA and VGA, Google Groups