There is some problem with this card with the P5W DH, and I'm not sure about other crossfire/conroe board. But it doesnt run in 2 gpu mode sometimes, and appears to be completely random. I test this by running Aquamark randomly and sometimes it would show that both gpus are working but other times it is not. Again this is random, I have no idea how to pernamently make it run the way it's suppose to. The only way to resolve it for me when it does that is to go back into the Nvidia control panel, set to multi-display mode, and then set it back to multi-gpu mode. If anyone has the same setup can confirm this or have a solution would be great.