Okay then lets get started shall we?
You already have a GPU and a case correct, or do you just want a 7600? I'm also guessing that your going to take the DVD drive out of your current computer and also the harddrive.
So here goes.
Processer:
AMD Athalon x64 3700+Motherboard:
ASUS A8N-SLi PremiumRAM:
OCZ Enhanced Latency 1GB PC3200Total $495
Now if you need said itoms (case, HDD, GPU, Optical drive)
HDD: [url=http://www.newegg.com/Product/Product.asp?Item=N82E16822144415]WD Caviar 160GB SATA3
DVD Burner:
Samgsung Dual layer DVD burnerGPU:
eVGA 7600GTNew Total $781
Now that motherboard is a bit over the top, and a lesser one can be bought if the extra $30 is too much.
Anyway with the exception of the GPU, for a little less than $800 thats probibly what I would build.
Cheers
Cameron