Pretty much any card with that supply. Might want to possibly consider dropping in an x4 while you're at it. The 965 can be had for @ or < $100 right now.
You might get a bit of bottlenecking from you CPU but with either card you listed you should get nice FPS in most titles.
Upgrade to a Phenom II X4 while there are still some available, and get whatever GPU you can afford. If you have a specific budget, we can suggest some cards that are best bang-for-your-buck.