XGA+ stands for Extended Graphics Array Plus and is a computer display standard, usually understood to refer to the 1152 × 864 resolution with an aspect ratio of 4:3. Until the advent of widescreen LCDs, XGA+ was often used on 17-inch desktop CRT monitors. It is the highest 4:3 resolution not greater than 220 pixels (≈1.05 megapixels), with its horizontal dimension a multiple of 32 pixels. This enables it to fit closely into a video memory or framebuffer of 1 MB (1 × 220 bytes), assuming the use of one byte per pixel. The common multiple of 32 pixels constraint is related to alignment.
Historically, the resolution also relates to the earlier standard of 1152 × 900 pixels, which was adopted by Sun Microsystems for the Sun-2 workstation in the early 1980s. A decade later, Apple Computer selected the resolution of 1152 × 870 for their 21-inch CRT monitors, intended for use as two-page displays on the Macintosh II computer. These resolutions are even closer to the limit of a 1 MB framebuffer, but their aspect ratios differ slightly from the common 4:3.
XGA+ is the next step after XGA (1024 × 768), although it is not approved by any standard organizations. The next step with an aspect ratio of 4:3 is 1280 × 960 ("SXGA-") or SXGA+ (1400 × 1050).