This was driver related. Using a beta driver, my GPU clock pegs at the expected value. fps in GW 2 was not much improved though. It drops to low 40s in some situations. One theory is that indicates that the current situation is CPU limited not GPU limited. I am not sure on that, more testing would be needed.
I am having the exact same problem (SLI 560 TI's) and its frustrating as hell, however once in a while for no reason my clocks will go above the 40 to 50% mark on each to 60 to 80% and then i hit around 140 fps in the same spot if the frame lock is off , running 4 cores at 3.8 GHZ so its very doubtlessly a CPU issue please respond with any software fixes