Ubuntu Tip: CPR Frequency Scaling for Pentium IV on Linux

I was goofing off a little today, and I came across a method to set up CPU frequency scaling on Linux for Pentium IV processors. I didn't know that these processors even supported CPU scaling, so this is a nice surprise. I took information from a couple sites, and made my own little how-to for this:

1. Open a terminal window and type: sudo dpkg-reconfigure gnome-applets . You will see a warning about how it might be unsafe to run the cpu-freq selector program with root powers. Move the highlight to yes using the arrow keys, and hit enter.
2. Now, enter this command at the terminal window: sudo modprobe p4_clockmod . This loads the p4_clockmod module into the kernel, so it starts working immediately. If all goes well, you won't see any error messages returned. If you do get an error message, it means that your processor isn't supported by the p4_clockmod module. I'd suggest doing a Google search to see what module to use.
   
3. Now, you want the p4_clockmod module to run when your computer starts up, so add it to your /etc/modules file: sudo gedit /etc/modules . At the line p4_clockmod to the bottom of the file, save and close, and you're in business.
4. Last part is to add an easy method for controlling the CPU frequency. Since the GNOME desktop provides a gnome panel applet for that, it's what I use. Right-click on an empty spot on the panel, click "add to panel..", and drag the "CPU Frequency Scaling Monitor" down to the panel. By left-clicking on the applet, you can select among various options for your CPU speed.

That should be it. If you have any problems, leave me a comment and I'll see if I can help.
Thanks to Ubuntu Kung Fu and the Ubuntu Forums archive for providing the material for this how-to.