ATI Radeon clock speeds

[Terrahawk]

I just swapped out the motherboard in my R40 2723-26M for another one from a 2722-3GG. The motherboard is the same apart from the Mobility Radeon 7500, which should be quite an upgrade from the M6 Mobility Radeon on my previous motherboard.

I noticed though that when the laptop is plugged into AC, the clock speeds of the Radeon go to their maximum, which is expected according to the documentation I have read on PowerPlay. However, I am not sure of the proper clock speed of the Radeon 7500. Some sites say 270 MHz with 183 MHz RAM, and others say 270 MHz with 230 MHz RAM. The R40 defaulted to 183 MHz core, 183 MHz RAM speeds.

Just for fun, I installed ATITool and had a play to see how fast the Radeon could go. Over 300 MHzRAM speed, there were many 3D artifacts and over about 330 MHz core, the system locked up.
I settled on 280 MHz core and 280 MHz RAM speeds, which are just shy of 100 MHz higher than the default.

I ran 3DMark2001 and I got a score of 5629 (1.7 GHz Banias Pentium-M) which is significantly higher than the score at default clock speeds, which was 3505.

Has anyone else tried overclocking the ATI video chips in their Thinkpads? If so, how far did you get?

[ronbo613]

I've used ATI cards for many years and have an X800XT and 9200 in my PCs as well as the same "mighty Radeon 7500" in my T30. I prefer ATI Tray Tool with my ATI cards. I would advise caution when fooling around with the laptop graphics card. The reason your laptop card was artifacting was probably due to overheating. In the confined space of a laptop case, you can fry the video GPU without much effort. I use a Zalman GPU cooler and video RAM heatsinks on my X800XT just because it is a hard working card, not overclocked at all. Even if the Mobility 7500 was overclocked to the max(with proper cooling installed), the performance increase would be minimal.
3DMark2001 is the most even benchmark of the Futuremark software, 3DMark03, 05 and 06 are heavily weighted towards the graphics card, SLI, Crossfire and all.
I just resist the urge to fool around with the Thinkpad and let it run. You might look and see if Omega makes drivers for it, that's about all I would do.

[Terrahawk]

The performance increase from 183/183 to 280/280 is 60% That is not insignificant. The RAM and CPU are the same, the graphics chip/RAM clock speeds are the only difference.

I am very sure that the artifacts I observed during my brief overescalation of RAM clock speeds were not caused by heat.

What I am wanting to know is, that since IBM have apparently deliberately underclocked the Mobility Radeon 7500, how much success has anyone had at running it at its supposed proper clock speeds, or faster.