Hey..
The build suggested by Byte70 is great. The pc-gpu combo is awesome considering your budget. Though you may want to take a look at a better memory stick like the Corsair Vengeance or G.Skills Ripjaw series. And the issue with the motherboard is also pointed out. Take a look at Asus or Gigabyte boards. And finally just as a precautionary step, try and get a higher wattage PSU. Corsair is great, but try and go for the 600W or 650W.
If you get really tight with your budget and wanna future proof it, maybe you can try AMD rig. Depends on what is your requirment though for gaming Intel rigs are usually better.
Cheers mate.