CPU Scaling in 64 bit AMD laptops (Fedora)

I recently bought an HP Pavilion DV6000, with dual Turion 64 bit processors. I installed and tried different Linux distributions on it. I think I will mention later about my first impressions and experiences on the distros I tried, including Fedora, Debian, Ubuntu, Pardus, and Sabayon.

For today, I have only a few words on Fedora Core 6, x86_64 sub type:

The default kernel shipped with the iso DVD was simply crap! It kept freezing during installation and I had to disable the acpi daemon to be able to procede with installation.

As soon as I got through to the post-installation step, my first task was to boot it in “init 3”, changing the kernel options from the Grub menu. Otherwise, the system was not stable at all! A “yum update” from the console upgraded the kernel and a lot of other stuff. I fixed several other issues including wifi, suspend 2 ram etc., but these will be the topics of later posts.

To see whether CPU frequency scaling is supported or not was important to me as a laptop user. So you can do the following to see if things are alright on your system:

As root or by sudo’ing, type:

lsmod |grep cpufreq

Do you see something like cpufreq_ondemand?

If it’s not working, probably you won’t see it. Also, check your

/etc/cpuspeed.conf

In this file, make sure that your CPU freq scaling module name is not commented out and that you have something like this:

DRIVER=”powernow-k8″

Finally, restart your cpu freq scaling service:

/sbin/service cpuspeed restart

If it starts with no warnings and if you don’t get any messages in your system logs, chances are it’s working fine.

To see the current cpu info just type

cat /proc/cpuinfo

which will list all the vital information about your CPU(s).