it should be fine for most games exept maybe the most cpu intensive one and those that use only 1 or 2 threads...this gpu is nowhere near high end so youre looking at medium low settings in modrn games, wich will match the cpu power just fine..
I have a Phenom II X3 with my 6870 and games don't seem to be bottlenecked at all. So You'll be definitely fine unless ofc it's a CPU intensive game like Metro: Last Light or an RTS.