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Date:      Sun, 28 Jan 2007 15:07:15 +0900
From:      FK <>
Subject:   Re: Pentium 3 Clock Frequency Control
Message-ID:  <>
In-Reply-To: <>
References:  <> <>

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Dear all,

Thank you for your information.

Subject: Re: Pentium 3 Clock Frequency Control
Date: Sun, 28 Jan 2007 00:14:54 +0500
Message-ID: <>

applecom> FK <> wrote:
applecom> > Is it posible to control Pentium 3 clock frequency on FreeBSD?
applecom> > The purpose is to reduce the power consumption and lengthen battery
applecom> > life.
applecom> > In addition, how can we know what speed of cpu clock frequecy a cpu
applecom> > supports and what speed a cpu take at any given time? I suppose
applecom> > that a command which returns each information exist.
applecom> > Well, a couple years ago I patched to, if I remember correctly,
applecom> >  5.4 kernel and it made this need possible at least on Pentium M.
applecom> > I tried to find the web page but I failed.
applecom> > I am using FreeBSD6.0-RELEASE now.
applecom> Look at
applecom> Hope it helps.

I thought cpufreq.ko is a driver for cpu frequecy control, 
as its man page says. I loaded it to the kernel, with nothing changed
like below.

The output of my sysctl is differen from the website you showed me. The
sysctl of his mentioned acpi, which I disabled. I chose apm, because
it turned off the TFT backlight, which acpi failed. TFT backlight off
is also critical for the power-saving.

Any suggetions?

Still, I would like to know what cpu the cpufreq.ko supports. Its man
page does not say anything. And I would like to know whether we have
any other drivers on which this function is implemented.


-- Quoted from Man --
     The cpufreq driver provides a unified kernel and user interface to CPU
     frequency control drivers.  It combines multiple drivers offering differ-
     ent settings into a single interface of all possible levels.  Users can
     access this interface directly via sysctl(8) or by indicating to
     /etc/rc.d/power_profile that it should switch settings when the AC line
     state changes via rc.conf(5).
-- End of quatation --

>sysctl dev.cpu
dev.cpu.0.%driver: cpu
dev.cpu.0.%parent: legacy0

>sysctl dev | grep apm
dev.apm.0.%desc: APM BIOS
dev.apm.0.%driver: apm
dev.apm.0.%parent: legacy0

Id Refs Address    Size     Name
 1   12 0xc0400000 3d5e94   kernel
 2    1 0xc07d6000 51f8     snd_t4dwave.ko
 3    2 0xc07dc000 1d9c8    sound.ko
 4    1 0xc07fa000 57ac     apm.ko
 5    2 0xc15d7000 c000     ipfw.ko
 6    1 0xc15e5000 4000     ipdivert.ko
 7    1 0xc163b000 4000     logo_saver.ko
 8    1 0xc1643000 15000    linux.ko
 9    1 0xc2011000 8000     cpufreq.ko

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