XGA 

XGA (4:3) compared with the other display standards.

XGA, the Extended Graphics Array, is an IBM display standard introduced in 1990. Today, 1, but the official definition is broader than that. It was not a new and improved replacement for Super VGA, but rather became one particular subset of the broad range of capabilities covered under the "Super VGA" umbrella.

The initial version of XGA expanded upon IBM's VGA, adding support for two resolutions:

Like its predecessor (the IBM 8514), XGA offered fixed function hardware acceleration to offload processing of 2D drawing tasks. XGA and 8514 could offload line-draw, bitmap-copy (bitblt), and color-fill operations from the host CPU. XGA's acceleration was faster than 8514's, and more comprehensive in that it supported more drawing primitives and XGA's 16 bits per pixel (65,536 color) display-mode.

XGA-2 added true color mode for 640×480, 1024×768 support for high color and higher refresh rates, and improved accelerator performance. All XGA modes have a 4:3 aspect ratio rounded to 8 pixels.

XGA should not be confused with VESA's EVGA (Extended Video Graphics Array) which was released at a similar time.

Contents

Clone hardware

XGA hardware was not cloned as extensively as VGA hardware. Nevertheless, at least one graphics company made several XGA-compatible chips, the IIT AGX.

Comparison chart

Name x
(width)
y
(height)
Pixels
(×1 Million)
Aspect
Ratio
Percentage of difference in pixels Widescreen
version
Typical screen
sizes
VGA SVGA XGA XGA+ SXGA SXGA+ UXGA QXGA
VGA 640 480 0.31 1.33 0% −36% −61% −69% −77% −79% −84% −90% WVGA
SVGA 800 600 0.48 1.33 56% 0% −39% −52% −63% −67% −75% −85% WSVGA
XGA 1024 768 0.79 1.33 156% 64% 0% −21% −40% −47% −59% −75% WXGA 15"/ 38cm
XGA+ 1152 864 1.00 1.33 224% 107% 27% 0% −24% −32% −48% −68% WXGA+ 17"/ 43cm
SXGA 1280 1024 1.31 1.25 327% 173% 67% 32% 0% −11% −32% −58% WSXGA 17–19"/ 43–48cm
SXGA+ 1400 1050 1.47 1.33 379% 206% 87% 48% 12% 0% −23% −53% WSXGA+
UXGA 1600 1200 1.92 1.33 525% 300% 144% 93% 46% 31% 0% −39% WUXGA 20"/ 51cm
QXGA 2048 1536 3.15 1.33 924% 555% 300% 216% 140% 114% 64% 0% WQXGA 30"/ 76cm


See also

References

This article was originally based on material from the Free On-line Dictionary of Computing, which is licensed under the GFDL.