I'm considering either the dual 2.0 or the dual 1.8 PM. If I bought the dual 2.0 I'd get the Radeon 9600 graphics card. If I bought the dual 1.8, I'd get the top of the line nVidia 6800 card. I figure that makes the dual 1.8 PM $100.00 more expensive than the dual 2.0. So... my question, which is the better buy? (Assuming all other stats the same 160GB HD, 1GB ram, airport extreme, BT, etc.) I don't figure on trying to play many games (maybe one in a blue moon). I plan on using my xBox for that (perhaps the PS3 when it comes out).