[ltp] SpeedStep? - ACPI "throttling"

Tony Whitmore linux-thinkpad@linux-thinkpad.org
Tue, 13 Apr 2004 18:20:08 +0100


Jordi G. March wrote:
> Well, that's a good point... How did you manage to get full power even 
> without AC cord plugged in?

I didn't :) The laptop would stay at 800MHz if it was started with the 
mains off. Turning the power on later didn't make any difference.

If the laptop was started with the power on, it would run at 1.4Ghz at 
all times, even if the power was turned off later.

Come 2.6, however and it was just a case of selecting the 2 or 3 
relevant options before compiling the kernel. After reboot my CPU speed 
monitor shows the CPU idling at 113Mhz most of the time, unless it needs 
to speed up a bit. Battery life has been dramatically extended as a result.

HTH,

Tony