Display Card 824 GC: Compatibility With Other Video Cards



How do I use a Macintosh Display Card 8*24 GC in conjunction with a third-party
video card? Specifically, I'm trying to use a RasterOps Video ColorBoard 364
with the Macintosh Display Card 8*24 GC. With both cards in a Macintosh, only
one card works -- depending on which slots I've put the cards in. The card
that's in the slot closest to the power supply is the one that's recognized,
while the other card doesn't work at all.

RasterOps says that the Macintosh Display Card 8*24 GC might not be releasing
control of the bus to other graphics cards. Is this what's happening?

The card nearest the power supply becomes the "bus master". If your
Macintosh Display Card 8*24 GC is in the bus master slot, it will take
control of the bus and prevent another card with a processor on it to run.

If your third-party card is in the bus master slot, the third-party card
may or may not release control of the bus, depending on its design.

Essentially, you can have only one accelerator card running at a time. If
you turn the acceleration of the Macintosh Display Card 8*24 GC off, you
should be able to use both video cards.



Published Date: Feb 18, 2012