This is a small app. someone put together that allows you to overclock your ATI card. It's a qt app., so you need the proper qt libraries if you want to use it on other DEs (libqt4-core, libqt4-gui, and libqt4-network should be enough).
The guy is just starting, so the app, is simple. A couple of sliders for the GPU and memory frequencies (with Overdrive locks), a slider for fan control, and a slider for GPU voltage control. The frequency sliders work; don't know about the fan (water block on mine), and did not test the voltage (but it does detect it correctly at least). Changes are not persistent, so clocks will revert back to defaults once you reboot your system.
Any card that is supported by fglrx and has Overdrive support should work. The developer is looking for feedback on this, so if you do use it let him know how it works for you.
Forum discussion and download links
ATI overclocking GUI
05-27-09
ATI overclocking GUI
