well u can try download riva tuner and check (might have bad results)
so far leadtech had the best success and gigabyte were fine. the fact that its an OC shouldn't make any differance but be prepared that u might have to underclock it if it has 8 pipes
I have no idea where to check in RivaTuner. I don't know whether to go into driver settings or target adapter, or what. Plus, can you really unlock them in RivaTuner? Cool.
EDIT: I figured out that mine doesn't have the extra pipelines to unlock. Stupid card. Anyway, thank you for your help.