My computer can run all games I've ever thrown at it, even Crysis on high. Without the blu-ray player and 1tb hard drive, I paid $800 about 6-8 months ago and I an very happy with it. Click on my name and check out my setup if you'd like.
Brings the total to: $982. The 5770 is good for gaming at anything up to 1900x resolutions. The 5850 is better for 1900x. By dropping to the 5770, you'd be able to afford a good monitor that would still allow great gaming performance from the computer.