I found this thread thru a Google search. CraigRT knows this already from another thread; I was looking (very seriously!) at the Tyan K8W. Over in the 2CPU.COM forums there is a thread a mile long about the K8W and it's issues with ATI9800xx cards.
Seems the AMD 1851 AGP Tunneling Chip on it doesn't play well with these video cards. Basically, you're lucky if it boots.

NVidia cards have no probs.
This is the reason why I didn't get that board and won't unless they fix the prob.
OTOH, I can't wait to see how the DK8N does! I may have my dually Opteron yet.

The board looks like freakin' GOD, man.

Just like the K8W. If it works w/ATI cards, I'm in.