my suggestion for case without spending much more then what you have selected.
HD is the same one I use
suggest this PSU. Id never trust anything under 650 when doing a custom build. I personally use 750-850's in mine however trying to stay close to your price.
The CPU will work, however Id rather spend the extra and get dual GTX460s since they are cheap as crap now and perform great. I ran dual GTX460 twin frozrII's from MSI. I payed i think 180 each when i got em, but ive seen them down around 100 bucks ea. even with cheap cards, running 2 of em will give you better performance then the on board card. Especially seeing in the reviews where most games are averaging 25-35 FPS... thats not good at all, and alot of those arent real demanding games either. Although all comes down to what kind of games you are planning no playing. If wanting to run BF3, I def wouldnt suggest the CPU choice.