Yes, that is a very nice gaming rig, but you know that you can "Unlock" the 6950 into an 6970? You would have a nice ~20% performance boost. That unlock is very safe and have an 97% of succes rate.
Also, if your card can't output to over 120Hz, you will still get tearing if you don't have V-Sync enabled. (V-Sync doesn't just limit the frame to 60)