if you like shooters, BF3 would probably be an easy suggestion. that way you can get ready for BF4
I run an XFX R7800 series card with an AM3+ quad core processor at 4.2ghz without any overclocking and can run BF3, Bioshock Infinite, and any other game I have on highest possible settings with a solid 30 fps. Borderlands 1 and 2 are fun, especially with coop partners that aren't trying to rush through the game. Dishonored, Tomb Raider, Crysis 3.