As per topic, if you have say a GT OC and a GT card (different manufacturers, different clock speed, same GPU), with the new drivers (since this is now allowed), will one scale down so they both perform at the same speed? Or will you be able to have the OC one running faster?
More aboutdoes speed scale drivers
Clock speeds are set in the card's BIOS, not in the drivers.
I have never heard of a driver preventing overclocking a video card, unless it is an extremely buggy driver.