I have two AMD 6950s that I use for mining and gaming which were able to Crossfire well originally. After a reinstallation of Windows 7 Professional 64-bit, when Crossfire is enabled, starting nearly any modern game (IE: Metro 2033, Crysis 1/2/3, etc) gives a stop error pointing to the infamous atikmpag.sys. Crossfire still works in Ubuntu 12.04 32- and 64-bit.

I've tried using various versions of CCC - pretty much everything 12.x and 13.x so far - to no avail, netting the exact same problems as before. I'm not sure what else - besides a reinstallation - would help.

For the record, one of the cards is Visiontek's 1GB card, while the other is Sapphire's 2GB "Dirt 3 Edition" card.

Any insight?