If you want it under$600 then I'd say you got a decent build.
I recommend the AMD Phenom II 965 or A8-3850. Both are quad core CPUs.
The HAF comes with two 120mm fans. To keep your case cool you should buy one more case fan for the side.
Actually the Pentium G850 + 7850 is a good combo for under $600. The 965 is a really aging CPU and the APUs aren't really meant for serious gaming.