Dead Space is ported and I know many people who had a ton of problems. There is no dust in the GPU or any build-up because I just put everything into a new case and cleaned it.
Every other game that I play, Metro 2033, BC2, Black Ops, Dirt 2, all work perfectly. Sounds like it is the game to me, but don't know how to fix it! I played around with CCC, thinking that maybe it was the overclocking, but I even underclocked it, and it didn't work. I will edit some of the 3D settings and see.