Ah okay, thanks
I don't think I can increase the voltage, don't you have to BIOS mod for that?
The reason I asked is because at the moment if I increase the clocks anymore than I have them at now I get artifacts/crashing/freezing. However, when I set the fan speed to 100%, which cooled the core down significantly, I managed to get to 740MHz without any artifacts etc. Then I set it to 750MHz and it crashed so I restarted and tried setting it incrementally back to 740MHz with the core temperature at around 80C. This made it crash at 730MHz or so when with a cooler card I had no problems at this speed.
Based on that, do you think it would be worth me getting a new cooler? This is also partly because of the noise. I've been looking at the AC Twin Turbo Pro and some of the offerings from Zalman.