This utility worked perfectly from the initial install. By lowering the "thermostat" on the PowerBook G4 it allows the fans to run at a higher speed and kick in sooner. This successfully cools off the laptop.

I used to have to take breaks from writing because my G4 would get so hot it was unbearable on my lap. Now I've set the "thermostat" to 40 degrees Celsius and I can work comfortably for hours with the laptop on my lap.

Note: The temperatures are in Celsius. It would have been nice to be able to switch to Fahrenheit but that's a minor issue.

Expect the fan noise to be higher since the fans will run at a higher speed to move more air through the computer.

Finally be very careful about setting the temperature, make sure it's not higher than factory settings.