Folding can be run on SLI cards with a little work. I do not think Xfire works with Folding though. I am not running the cards in Xfire, but it really just looked odd without the cable in there When its all setup, one card will be free for WCG GPU Beta WUs and the second card will have the new F@H client running. That configuration should work 100%. In other news, with the unlocking features enabled in the BIOS there is a fourth core recognized. Will have to wait until I get an OS installed for further testing.