Cpufreq

How can i set the frequency (manually or automatically) for athlon xp mobile processors? I have heard there is an utility(?) called cpufreq to change the voltage of the core. But is this cpufreq a part of acpi project?

Thanks in advance
slave01

-------------------------------------------------------
This sf.net email is sponsored by:ThinkGeek
Welcome to geek heaven.
http://thinkgeek.com/sf