X-bit labs (http://www.xbitlabs.com) has posted an article called "ATI RADEON 8500 Extreme Overclocking Experience".
Inspired with the successful NVIDIA Titanium graphics cards overclocking, we decided to undertake some extreme overclocking experiments with its No.1 competitor - ATI RADEON 8500. After some modifications, we managed to increase its performance in Quake3 Arena and 3DMark 2001 by some 20%-25%. Want to follow in our footsteps? Reading our review is the first move of yours then!
FULL STORY @ XBITLABS (http://www.xbitlabs.com/video/radeon8500-overclocking/)