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Super Video Graphics Array or Ultra Video Graphics Array,〔(Ultra Video Graphics Array (UVGA) )〕 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. 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." 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), 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 colors. It was quickly extended to 1024x768 8-bit pixels, and well beyond that in the following years. Although the number of colors 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 color. In consequence, so far as the monitor is concerned, there is no theoretical limit to the number of different colors that can be displayed. 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 colors 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-color 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, 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 == Some of the early SuperVGA manufacturers (in parentheses, some of their models, where available) were: * Ahead Technologies ''Not related with Nero AG (formerly Ahead Software)'' * Amdek (VGA ADAPTER/132) * AST Research, Inc. (VGA Plus (rebranded Paradise)) * ATI Technologies (VIP (82c441 (1987)), VGA Wonder) * Chips and Technologies (82c441 (1987)〔) * Cirrus Logic (CL-GD410/420 (1987)) * Compaq (VGC Board) * Everex * Genoa Systems (Genoa VGA 5100-5400 (ET3000)〔http://pdos.csail.mit.edu/6.828/2008/readings/hardware/vgadoc/ADAPTERS.TXT〕) * Orchid Technology (Designer VGA (ET3000), Pro Designer Plus) * Western Digital's Paradise Inc. (VGA Plus (PVGA1 (1987)),VGA Plus 16, VGA Pro) * Sigma Designs (SigmaVGA (ET3000)) * STB Systems (VGA Extra/EM (ET3000 (1987))) V-RAM VGA (1988)) * Willow (VGA-TV/Publisher's, VGA-TV + Genlock) * Trident Microsystems (TVGA8800, TVGA8900, and TVGA9000 series) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Super video graphics array」の詳細全文を読む スポンサード リンク
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