Kepler clocks and voltages are not static, they are dynamic. So they will automatically adjust on the fly, depending on the load required (or not) The card will also downclock if the horspower isn't needed.
Try increasing the GPU clock offset, or Boost Potential by +100MHz, this is a target speed, not a guarantee, And slightly increase the Power Target to allow the card to increase the voltage automatically and account for higher clocks.
Overclocking on Kepler provides diminishing returns because the GPU Boost is essentially already overclocking the card for you. Chances are you won't be gaining much, depending on the Boost Clock and Boost Potential of your particular card.
most 660's will max out @ Base Clock of 1135MHz, 1788MHz Memory, and 1213MHz Boost Clock.
Edited by Braegnok, 26 January 2013 - 01:18 PM.
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