Centrino CPU Frequency Scaling
 

Hi all,

I have Centrino 1.6GHz on a Thinkpad R51. When running with Windows, the frequency can reach the lowest point @ 221MHz, and the fan barely spins.

How can I reach the same frequency with OpenSuSE 10.2? I tried the YaST powersave module. But the lowest frequency could only down to 600MHz.

Many thanks!

To see what frequencies are available:
My Centrino 1.8GHz also goes as low as 600MHz, no lower. May be a limitation in the cpufreq code. When I tried FreeBSD, after a lot of fuss I got it down to 200MHz, which was nearly unusable.

I'm not sure that you can go lower, but you can edit the values in the files in /sys/devices/system/cpu/cpu0/cpufreq/ (be careful)

Hi,

I tried to edit the files 'cpuinfo_min_freq' and 'scaling_min_freq' under /sys/devices/system/cpu/cpu0/cpufreq with echo command:

and

But it seems doesn't work. The 'cat' replies the value remains at 600000.

How could I edit those two files? :confused:

You probably just can't. It might be part of the cpufreq code.

cpufreq has its own mailing list you could try, they'd definitely be the most knowledgeable:

http://www.kernel.org/pub/linux/util...q/cpufreq.html

Howdy,

Thanks for your reply and the link you gave to me!

You are right.I think the lowest frequency on this chip is 600MHz. Yesterday I put on NHC in Windows. The report showed the lowest frequency was 600, no less. But the funny part was that when I went to the "Properties" from "My Computer", the Windows showed me 221MHz only, which was less than half of the real frequency. duno why...

:rolleyes: