Nekraks:
Your not alone there matey, i've got exactly the same issue happening. I think it is an overheat prob but this is the first game that's doing it. I too play CoD4 and Empire with no probs, but this is killing the PC.
I'll try clearing out the fans and see if that does the trick. Funnily enough mine a Q6600 chip as well.
Real sod considering I was enjoying playing the game.