How to control CPU frequency

Question

On Lenovo T400 and Ubuntu 10.10, I am using CPU Frequency Scaling Monitor 2.30.0 on the panel to show and control CPU frequency.

My CPU frequency by default will change according to load. But I want to make CPU work at the lowest level and so I choose 800 MHz in CPU Frequency Scaling Monitor. After a few seconds, however, it automatically changes back to Powersave or Performance mode which has automatic adjustment to CPU frequency.

I was wondering how to actually make CPU work at the lowest level? Thanks!

PS: On Acer Aspire 5000 and ubuntu 8.10, I can use CPU Frequency Scaling Monitor to control CPU frequency as I wish.

Answer 1

Follow the steps:

sudo apt-get install rcconf 
sudo rcconf

Search for

ondemand

option and disable(un-check the check-box) it using space-bar.

Answer 2

man cpufreq-set. Quick answer:

sudo cpufreq-set -r -d MINIMUM-FREQUENCY -u MAXIMUM-FREQUENCY

You might try the exact command:

sudo cpufreq-set -r -d 800MHz -u 1GHz