If you're going to be using the PC for intensive graphics rendering, go with a Quad Core CPU.
Intel Q9550 $220
http://www.newegg.com/Product/Produc...82E16819115041
ASUS P5Q Pro Turbo $130
http://www.newegg.com/Product/Produc...82E16813131377
Are your Hdd/optical drives IDE or SATA.
Newer Mobo's have One IDE connector (up to two devices).