OverclockingTo find the maximum overclock of our card we used a combination of GPUTool and our benchmarking suite.
The overclocks listed here were achieved with the default fan and voltage 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 overclocks of our card are 870 MHz core (16% overclock) and 1050 MHz Memory (31% overclock). Very nice! With such an overclocking potential the card can easily beat NVIDIA's GTS 250 and come quite close to the HD 4870.
I noticed one thing during overclocking, which is that the card crashes when certain core / memory clock combinations are set. The crash is caused by a bug in the BIOS which calculates wrong clock settings for the given input clocks. If you encounter this problem, just increase the other clock you were not changing. So if you increase core and it crashes, change memory by 10 MHz up or down, then you can set the core clock you were initially trying to set - and vice versa.
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 from overclocking is 22.7%.
The temperatures are very very low under both idle and load. Powercolor's engineers should have used this opportunity to reduce the fan noise levels some more.