What is your price range? Budget go with a 7600GT. If you have the money go with a 7900GT(X).
A+, Network + , HP Certified Tech and MCP
Specs: AMD Phenom II X6 1095T, Asus M477TD, 8GB GSkill Ripjaws DDR3 1600 7-8-7-24 1T, 128GB Crucial M4 SSD, ATi HD4650, W7, 27" HL272 Monitor