Quote Originally Posted by AgentGOD View Post
A moderator on EVGA said the shader clock goes higher when you have better cooling.
That's exactly right. If I keep my core temp low to mid 60s I can run 1566 shader, otherwise the limitation is 1512.

Others with vmods and chilled water setups have run upto 1674mhz shader on their GTX280s. Temps were down in the mid to high 30s though.