Editing IBM PS/2 (section)

====VGA video connector====
All of the new PS/2 graphics systems (whether MCGA, VGA, 8514, or later XGA) used a 15-pin [[D-sub]] connector for video out. This used analog RGB signals, rather than four or six digital color signals as on previous CGA and EGA monitors. The digital signals limited the color gamut to a fixed 16- or 64-color palette with no room for expansion.  In contrast, any color depth (bits per primary) can be encoded into the analog RGB signals so the color gamut can be increased arbitrarily by using wider (more bits per sample) [[digital-to-analog converter|DACs]] and a more sensitive monitor. The connector was also compatible with analog grayscale displays. Unlike earlier systems such as [[IBM Monochrome Display Adapter|MDA]] and [[Hercules Graphics Card|Hercules]], this was transparent to software, so all programs supporting the new standards could run unmodified whichever type of display was attached. On the other hand, whether the display was color or monochrome was undetectable to software, so selection between application displays optimized for color or monochrome, in applications that supported both, required user intervention. These grayscale displays were relatively inexpensive during the first few years the PS/2 was available, and they were very commonly purchased with lower-end models.

The [[VGA connector]] became the de facto standard for connecting monitors and projectors on both PC and non-PC hardware over the course of the early 1990s, replacing a variety of earlier connectors.