I am looking at building a machine dedicated for gaming with Intel Core 2 Extreme 2.93 Ghz QX6800 with 8 GB Corsair GTX 6 2,625MHz RAM ;and ASUS P5KPL-AM/PS Motherboard. The problem is I am not able to decide on the Graphics card between NVidia EVGA GeForce GTX 660 SUPERCLOCKED and And SAPPHIRE AMD Radeon HD 6870- Does anyone have suggestions?