Gaming Computers which is better?

You're wasting money on both of those computers. Get a better video card and/or a weaker cpu. It'll cost less or you can get a much better gaming computer for the same price. I suggest the 965BE or 955BE with GTX 460 if you want to go cheaper. Or if you want to spend the same amount of money, get one of the suggested CPUs with a GTX 570. The 460 route will be around 10% better than your setups, and the 570 route will be almost double the performance of your i5/550 or x6/5770.