OverclockingTo find the maximum overclock of our card we used a combination of ATITool's successor, Furmark and our benchmarking suite. We synchronized the clocks of both cards for overclocking testing.
The overclocks listed here were achieved with the default fan settings as defined in the VGA BIOS. Please note that every single sample overclocks differently, that's why our results here can only serve as a guideline for what you can expect from your card.
The final overclocks of our card are 693 MHz core (20% overclock) and 1207 MHz Memory (21% overclock). This overclock is simply stunning and shows that the GTX 295 design has quite some clock headroom left. However, my guess is that NVIDIA limited the frequencies to stay within certain thermal and power budgets so that the TDP of the card won't be too high.
Overclocked PerformanceUsing these clock frequencies we ran a quick test of Call of Duty 4 to evaluate the gains from overclocking.
The actual 3D performance gained is 16.3%.
For a dual GPU design these idle temperatures are comfortably low. I would have preferred to see slightly higher idle temperatures with quieter fan settings. Under load the temperatures rise considerably, yet are still far from anything that's cause to worry. It is also interesting that 20% overclocking only increases the temperatures by about 4%.