ive got a gtx 660 (gigabyte GV-N660OC-2GD) and a fx 8320 (can push it to 4.2ghz) wondering if i get another 660 for christmas where the bottleneck will be? ive only got 4gb RAM at the moment so im expecting a flaming here lol (upping it to 8gb hopefully before christmas) thanks in advance peeps