Depending on your budget, I'd wholeheartedly recommend the Q6600 option. I myself just bought the parts for a machine (Q6600 OC'ed to 3ghz, 4gb RAM, 8800GT 512mb). This machine has been doing quite well on 5 boxing.

If you're going for a Q6600, consider getting http://www.clubit.com/product_detail...temno=A1938452 this version over the OEM version that you chose. The G0 stepping processor has shown to outperform other Q6600s and is much better for overclocking if that is even a faint possibility for you. For the extra $20, you can't go wrong.