5150/5151 Video Card??

Chuck Guzis cclist at sydex.com
Sun Aug 14 23:53:47 CDT 2016

On 08/14/2016 09:21 PM, Fred Cisin wrote:
> That one has a lightpen connector, which his dorsn't. Not usually
> important, but it might have other differences, such as different
> functions for the switchrs.

Take another look--the one in the photo has the header in the same place
as that in the cited drawing.

Taiwanese makers were extremely, er, incestuous, back in the day.

The other telling thing is that there's no crystal/XCO on the board.
CGA cards, generally don't have one--they take their timebase from the
14.318 MHz ISA bus signal.  MDA/MGA cards all have their own timebase
(crystal/XCO).  EGA cards may have several.


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