some options
EVGA 01G-P3-1556-KR GeForce GTX 550 Ti (Fermi) FPB 1GB 192-bit GDDR5
requires 400W psu
http://www.newegg.com/Product/Product.a ... 6814130625with your price range and current card you will be hard pressed for any dratic performance increases, the 550 ti is about as cheap as you can go and still be worth the upgrade other wise it would be better to save up till you can spend about another $100 more