As with nearly all performance-oriented components, I wanted to see if the new kid on the block had any overclocking potential. Since the XTX model is currently the fastest product in the Radeon corral, I wasn't expecting a whole lot of headroom in my attempts. From the default settings of 650MHz core and 775MHz memory, I was able to overclock to 679/797. While not a huge increase, we're at the top level of performance anyway and I was still able to get some more frames out of the test suite. These two graphs will give you an idea what I mean:
When testing the overclocked board, I used only the 1600x1200 resolution. This just made it simpler to keep everything clear since all the OC testing was completed at one resolution. As a rule, I was able to attain an extra 3-4% in all tests.
For those who have not seen my overclocking criteria before, I only accept a value if there are NO artifacts and glitches. If any sort of corruption shows up on screen, I disregard the speed and reduce it until I get the maximum speed with no discrepancies. In the case of the GeCube board tested, this was the stated 679/797MHz speed mentioned.