Re: $640 new build
How much gaming, if any, will be done with this machine? If little then you are good with the 4770 and you can definitely step down from 750W to 550 and be well off. If moderate or heavy gaming, I would suggest a better graphics card. Everything else looks fine.
edit: Also, don't forget a optical drive!
PII 940 :: 5870 :: Rage powered