I have this same exact issue. Right now I am running a GTX570 SLI setup. This game heats them up like no other game does. The usual temperature while playing (even inside the character screen!) is about 70°C for one of my Graphics cards and 60°C for the other. My cpu goes up as much as 60°C. That itself is already way higher than usual but that's not all. Sometimes, randomly, without any obvious reason, they all heat up a whooping 10°C more. Peaking the graphics card at 80°C.