The Macintosh AV Series computers, including the Power Macintosh AV models, cannot display or capture 8-bit color video on displays using a resolution greater than 832x624 (17-inch, 19-inch, 20-inch, and 21-inch).
The reason is both VRAM and other on-board video circuitry are not fast enough to transfer the 8-bit color video data to the screen on larger monitors and the CPUs are only fast enough to dump the luminance data, so only 8-bit monochrome (grayscale) video can be displayed or recorded.
Article Change History:
13 Nov 1995 - Clarified type of video and Macintosh models.
24 May 1995 - Clarified black and white, not color capture.
18 Jul 1994 - Added other monitor sizes and reference to Power Macintosh.
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