Stopping Thinkpad T60 High-Pitched Squeal

After installing Ubuntu on my T60, I realized it was making this annoying, extremely high-pitched squeal. I found that it only squealed when it wasn’t plugged into the wall. After Googling a bit I found that I could stop it by setting the max_cstate. I think that this has to do with the CPU’s power consumption. At lower consumption levels it emits the squeal.

Anyhow, running the following command seemed to stop the screeching. The default is 8.

echo 2 > /sys/module/processor/parameters/max_cstate