Color Graphics Adapter
Video standard released together with the PC XT and was the first graphic system with colors on the PC. In its highest resolution mode, CGA allowed a resolution of 640x200 pixels with only two simultaneous colors. Another popular CGA resolution was 320x200 pixels with four simultaneous colors.
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CGA video card.
After a while, video card manufacturers started to build ”dual“ video cards, which were, at the same time, MDA and CGA, selectable through a jumper, also allowing Hercules (HGC) mode. You can easily differentiate a standard CGA from a dual video card: by its size (compare pictures). Another detail is that dual and MDA cards also came with a parallel port, which wasn’t found on CGA cards. CGA, MDA and EGA cards used a 9-pin female D-shell connector.
Dual video card.
Notice that you must install a CGA video monitor to a CGA card in order to make the system work. CGA video cards don’t work with other types of video monitors like MDA, EGA, VGA, SuperVGA, etc.