It ran horrible on my 6800GT P43.0ghz and it runs horrible on my 7900GTO E6600 C2D. Its unplayable, the stuttering in the game is unforgivable. I tried to diagnose it and test this and that driver, deleting here and there no success. I gave up after trying to play it anyway, and the story didn't catch me either, so i think of it as a waste of $40 bucks. I haven't had very many bad game buys, at least in my adulthood. Thats why this one tops it.
That is strange, what res are you trying to play it on and did you max everything out entirly? I've had no problems running it on my old P4 3.2 GHz and 7800 GTX.