The Phenom ii x3 720 will provide more than is needed to keep a 8800gt feed if that's what you mean. In fact it can easily run better cards than that.
As ct1615 has said provide us with some details and I'm sure we can help you much more.
I havent tried to play any games, like I said I'm in the process of building a computer and I was just wondering if it will handle little bit older games.