Overclocking
We used ATITool to automatically find the maximum core and memory clocks of our card.
In the end the card runs completely stable at 631 MHz Core (1 % overclock) and 1015 MHz Memory (1.5 % overclock).
The overclocks are very small, but you have to consider that the card is already running above the spec. It seems that EVGA has carefully selected those clocks to be very close to the maximum that is possible with those cards.
On one hand this means that you can not gain additional performance by overclocking, on the other hand it means that you won't have to waste your time with this because the card is already running at its optimum.