What I think he should do since he is strictly on that budget of $450 would be to get a cheaper motherboard and then get a 6800gs video card that is the best performance card out there for the money.
Since your looking at tigerdirect I found this.http://www.tigerdire...1647240&CatId=0
Do NOT get the 6600 if you do he will wish he never would have upgraded. The 6600 is slow especially for bf2 in general. The 6800gs will run all games at high settings and it is equal to that of a 6800gt. The 6800gs is like 1-2% slower than a 6800gt. Do not get the 6600, that would be the worst mistake for the money, that card is not worth that much.
I would not pay that much for a plane looking asus motherboard, look at gigabyte, msi, abit as they all make cheaper boards and high end boards also.
1. Pick a cheaper motherboard, in the end with the 6800gs the system will be way faster than with the 6600.
2. Buy the 6800gs
3. That case looks fine but it doesnt say anything about the voltage on the rails. You know that those kind of powersupplies included are cheap and may or may not burn out. Thats just a risk you have to take.
The processor is a fine choice, but the video card and mobo has to go for shure. The case would be fine probably.