To: linux-kernel@vger.kernel.org
From: mru@kth.se (=?iso-8859-1?q?M=E5ns_Rullg=E5rd?=)
Subject: Re: Selecting CPU frequency on Asus P4M laptop
Date: Thu, 27 Nov 2003 18:48:59 +0100
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mru@kth.se (M?ns Rullg?rd) writes:

> I have an Asus M2E laptop with a 1.8 GHz P4M CPU.  Using the 'acpi'
> cpufreq driver, I can select between 1.8 GHz and 1.2 GHz, thereby
> changing the power consumption.  If I boot the machine with the AC
> adapter disconnected, it starts off at 1.2 GHz.  After that, I can
> lower it to 800 MHz using cpufreq.  In short, cpufreq will be able to
> choose among one of two pairs of frequencies, which depend on the
> status of the AC adapter at boot time.
>
> Is there any way to change which of these will be used after booting?

Update:

I ran a speed test, "openssl speed", in the various modes, and it gave
the same results whichever way the machine was booted.  It appears to
be reporting/detecting incorrect values when the AC adapter is
unplugged.  Switching speeds with cpufreq does change the actual speed
of the CPU.

-- 
M?ns Rullg?rd
mru@kth.se

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