I would get a core 2 duo E8400 and Arctic Cooling Freezer 7 Pro CPU Cooler, on a P5Q-Pro, instead of the amd tri-core. The Wolfdale E8X00 chips are arguably some of the best performing chips in current games. The E8400 on overclockers will probably be E0 stepping, you could most likely do 4 ghz with the cpu cooler I mentioned.
The other parts people have listed I agree with, 4850 512 MB, whichever 4GB DDR2 1066mhz set is on sale, antec 300, etc
The other parts people have listed I agree with, 4850 512 MB, whichever 4GB DDR2 1066mhz set is on sale, antec 300, etc