professional graphics adapter (PGA)
The Professional GraphicsController (PGA) is an older graphics standard. Like the VGA format, it has a resolution of 640 x 480 pixels, but only a color depth of 8 bits, corresponding to 256 colors, out of 4,096 colors. The PGA format was developed by IBM in the 1960s. The PGA format is a further development of the Color Graphics Adapter ( CGA).