[ubuntu] Ubuntu 11.04 Natty disables CPU scaling and underclocks on Thinkpad T40p

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http://ubuntuforums.org – I have an IBM Thinkpad T40p with a Pentium M 755 2.0 GHz CPU. After upgrading to Ubuntu 11.04 from 10.10 the CPU is incorrectly underclocked to 598 MHz and cannot be adjusted, manually or automatically. When I boot off the old 10.10 live CD, CPU scaling and all the governors work again perfectly. I've tried loading every possible scaling module I could think of (acpi-cpufreq, speedstep-centrino, p4-clockmod, cpufreq_ondemand) and tried multiple scaling daemons and programs with no luck at all. I'm stuck at what to try next. The Gnome Panel CPU Scaling monitor says "CPU frequency scaling (Hardware)