I'm thinking of upgrading my gpu to a 7970 or 7950. My concern is that it may cause a bottleneck with my cpu (phenom x6 1100t, currently oc at 3.8). My current gpu is a 6950 (2gb). Would a cpu bottleneck be a concern with either of the 7900 cards. Also, would it be wiser, in the terms of price vs performance, for me to crossfire my 6950. Thanks!
Mobo: Gigabyte 990fxa-ud3
CPU: Phenom x6 1100t @3.8 with Antec H2O 920
GPU: His 6950 iceq x turbo 2gb @ 910/1425
Mem: Corsair Vengeance 16gb 1600 (4x4gb)
PSU: Corsair TX850M
HDD: 2x WD Caviar Black WD1002FAEX 1TB 7200 in Raid
Case: Silverstone Raven r02