I have the same system, with a 2600K instead of 2500K (but those perform the same in games) and I can play Witcher 2 at very high settings, Crysis 2 at Extreme with DX11 and high res texture pack and WoW on full ultra. (all @1920x1200)
Witcher 2 and Crysis 2 both net about 40FPS avg with these settings.