If it's only going to be 1 GTX680 - you don't need that big of a PSU 650W plenty.http://www.newegg.com/Product/Product.aspx?Item=N82E16817139012
Also, what is the main use for this computer? If gaming, you may want to save a bit on the cpu/mobo and get a ssd drive for your OS.
I'm gonna use it for gaming and some 3D animation(not alot). I also already have a Crucial M4 64gb!
Later, I am going to SLI, think that GS800 will be enough?