Comment 59 for bug 30557

I confirm that this problem still exists in Feisty, including the latest 2.6.20-16 kernel.

I'm running on a Compal DL71 with an Intel Pentium M 740 1.7 MHz CPU. Out of the box, the system was not doing any CPU throttling, always running at max CPU clock. I had previously run Breezy 5.10 which didn't exhibit any of these symptoms.

Some Googling later, I learned to remove powernowd and how to use the cpufreq-info and cpufreq-set tools. With the "ondemand" governor, the system didn't throttle at all. With the "conservative" governor, it did throttle propertly, however KDE's power management tool (package: kde-guidance-powermanagemet) kept crashing because it doesn't know about the "conservative" governor.

Long story short, I recompiled the kernel, configuring it for single CPU (no SMP) and the Pentium M cpu, and CPU throttling with the "ondemand" governor now works well. The following articles were helpful with the kernel recompile:
https://help.ubuntu.com/community/Kernel/Compile
https://help.ubuntu.com/community/Suspend2Kernel
https://help.ubuntu.com/community/CustomRestrictedModules