HowTo: Undervolt your notebook CPU for longer battery life

[cheaptrick]

the test werent giving me accurate Vids,
i got this 9:37 8:27 6:21 136:11
from cat /sys/devices/system/cpu/cpu0/cpufreq/phc_controls

my tweaked vids output was 6 6 1 1
echoed it, and was never able to boot up again in ubuntu until i undo the echo

[pressureman]

Module for latest Intrepid kernel, 2.6.27-4-generic (32 bit)

[Lure]

Did anybody build the module successfully for 64-bit Intrepid kernel? It seems that all positive reports are with 32-bit kernel...

When I try to build it myself, it fails to load with module format error.
If somebody would share a working 64-bit module, I would be more than happy.

[linkmaster03]

OK. I did everything and it was correct, up until I ran the script. It went all the way down to 0 and stopped.

Default VIDs: 40 34 30 25
Current VIDs: 0 34 30 25
Testing VID: 0 (700 mV)
..............................
Default VIDs: 40 34 30 25
Current VIDs: -1 34 30 25
Testing VID: -1 (684 mV)
./linux-phc-optimize.bash: line 161: printf: -1: invalid option
printf: usage: printf [-v var] format [arguments]


The lowest acceptable VID is 0.

Recovering CPU.
./linux-phc-optimize.bash: line 138: 11296 Terminated              burnMMX

Run this script again to continue the optimization.

Then when I tried to run the script again...

Load VIDs from 'phc_tweaked_vids'
> ERROR: Wrong VID count!

And it stops. Help?

[dman4486]

I have set everything up and run the script, but it will not run past my 3rd VID....it will not save the 3rd VID either.

here is what it saves:

16 8 30 26 22 18

why will it not continue?

when I run the script now, it goes down to "4" which would replace the 30 and crashes, but never saves the "4"

[dman4486]

i have set everything up and run the script, but it will not run past my 3rd vid....it will not save the 3rd vid either.

Here is what it saves:

16 8 30 26 22 18

why will it not continue?

When i run the script now, it goes down to "4" which would replace the 30 and crashes, but never saves the "4"

nobody?

[dman4486]

ok....figured out that issue, now how do I do step 5? I have rc0, rc1, rc2, rc3, rc4

[kasjak2000]

Hey guys,

I have a T5870 and my fids are:

root@x64ubuntu8041:~# cat /sys/devices/system/cpu/cpu0/cpufreq/phc_fids 
11 10 8 6 136 
root@x64ubuntu8041:~# cat /sys/devices/system/cpu/cpu1/cpufreq/phc_fids 
11 10 8 6 136 
root@x64ubuntu8041:~#

But I cant set down the processor to 600mHz, to 800mHz only

In the windows I can set the 600mHz (6x100) with rmclock successful, why not in linux?

Can anyone set down a C2D-processor to 600mHz? And if yes, how?

Regards
kasjak2000

[pressureman]

Module for latest Intrepid kernel, 2.6.27-5-generic (32 bit)

[patrickfromspain]

I'm running latest intrepid kernel (2.6.27-5-generic) succesfully with the phc extensions, and also was running 2.6.27-4-generic.

How I did? First I moved the acpi-cpufreq.ko original module to acpi-cpufreq.ko-original, then installed the linux-phc package from here http://ppa.launchpad.net/bonniot-use...n/l/linux-phc/ and rebooted.

After rebooting you can run sudo linux-phc-install and reboot, it should work fine. After that I removed the linux-phc package, since it seemed to give out an error when installed.

If I didn't move the acpi-cpufreq.ko module out of the way it gave me an error.

Hope it helps