Overclocking - hitting the magic 1GHz
Before we spill the beans on just how high the ASUS HD 6870 can go, it's worth noting that increasing juice to the maximum 1.35V brings the reference heatsink to its proverbial knees. While big, chunky and rather cool-looking, it's not the best thermal solution available for a PCB of this size. Indeed, we had to ramp up the fan to ear-bustin' levels to keep the 1.35V GPU from hitting 100°C.ASUS plays the overclocking game rather safe with the 15MHz jump from stock frequencies. Safety's thrown out of the window in the overclocking tests, however, as we dial the voltage to a moderate 1.2V, increase fan-speed to 45 per cent of maximum and then give the ASUS card some FurMark love.
Yup, you're looking at a Radeon Barts XT core running at 1,000MHz core with minimal voltage increase. The memory speed of 4,600MHz isn't too shabby, either.
