I don't play that, but I would use 4x/8x. I don't often go farther than that because you get diminishing returns after that, but if I can, I will. Unless you have a CRT, resolution bumps would probably be better before you go to higher settings. Since the textures in CS aren't that sharp, I would lower the AF from 8x to 4x if there was I needed performance. Then AA to 2x from 4x if I needed more performance.