After searching the web for information or reports, I have decided to install ATI tools for WinXP on my MBPro; but the version 0.24 was not working... Then I successfully installed ATI optimized drivers to replace those ones provided by Apple, then I installed ATI Tools beta version 0.25... And I immediately came to the conclusion that once again Apple dramatically underclocked the GPU of its notebook models. Indeed the Radeon X1600 in the MBPro is clocked a 310MHz / 278MHz (GPU and RAM respectively)! When looking on the web, I have found that many PC notebooks featuring this GPU have a 470MHz/470MHz setting...He managed to increase the clockspeed without a problem and his FPS in Counter Strike Source jumped from 61 to 97. They believe the reason why Apple underclocked the GPU is to make the notebook more silent. More details over here.
MacBook Pro Radeon X1600 massively underclocked
Posted on Friday, April 21 2006 @ 9:00 CEST by Thomas De Maesschalck