I have two (rather old) nvidia cards in my PC. * GeForce4 MX 420 * RIVA TNT2 I used these two cards to create a multi-seat setup with Fedora 8. (I used the proprietary nvidia driver). It worked great. When I upgraded to Fedora 9, I found that the proprietary driver wasn't supported, so I'm giving Nouveau a try. I'm finding that Nouveau can only deal with one card at a time, apparently. When I start X with the second card, the second monitor does not light up and X apparently locks up. Surprisingly, I couldn't find an existing bugzilla entry for supporting multiple cards, so now I'm creating one. Hope that's ok. (PS- I have some time in the next few weeks, and I'm a pretty good C programmer. Is this a bug that one could get into the code and fix in a few weeks, or are we talking major rewrite of the driver?)
As far as i know the problem is two fold (this is from hearsay and other impressions). One side of the problem seems to be that somehow the 2nd ddx(xorg driver) doesn't associate itself appropriately with the 2nd card/drm/kernel driver. This is not neccesarily a huge problem to fix, just a matter of finding it. The other side is that randr-1.2 doesn't support xinerama, so you will have to run two completely seperate xserver's. This is something that is well beyond the scope of a small'ish fix.
*** Bug 16597 has been marked as a duplicate of this bug. ***
*** Bug 16165 has been marked as a duplicate of this bug. ***
Nouveau should support multicard pretty well: http://nouveau.freedesktop.org/wiki/FeatureMatrix/
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