Linux kernel version 2.6.7 limiting cpu speed

From: john (jmuielewicznospam_at_yahoo.com)
Date: 07/28/04 

Date: Wed, 28 Jul 2004 07:10:21 -0500

I am running this kernel on a fujitsu lifebook B2175. I am having
trouble with power management. I have a 1.8Ah battery and am only
getting less than an hour of life. I should be getting at least 2.5 to 3
hours. this lifebook has a 500MHz mobile celeron and 128 meg of ram (I
know the ram is part of the problem--I need more--just haven't done it
yet--with 512 it should have preemo life). The question I have is how
can I limit the cpu speed in the kernel--I have found where I can vary
the speed but no place to limit the upper range. I would like to cut the
max back to 300MHz. That is fast enough for pretty much anything except
OO. Also is it better to use APM or ACPI? Is there a place to download
scripts for ACPI control? Thanks.