Re: Selecting CPU frequency on Asus P4M laptop

From: Måns Rullgård
Date: Thu Nov 27 2003 - 12:50:02 EST


mru@xxxxxx (Måns Rullgård) 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.

--
Måns Rullgård
mru@xxxxxx

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