Setting the trip_points for fan activity

Good morning everybody,

I recently installed Suse 10.3 on my notebook and I have a problem to control the fan cooling. The trip_points which control the fan activities are defined (by whom ??) in /proc/acpi/thermal_zone/THRM/trip_points as

critical (S5): 85 C
passive: 57 C: tc1=4 tc2=3 tsp=150 devices=CPU0
active[0]: 50 C: devices= FN1
active[1]: 40 C: devices= FN2

To avoid that my notebook runs hot I would like to change these values. With an old Redhat on my notebook I could just do
echo -n “85:0:50:40:35” >
/proc/acpi/thermal_zone/THRM/trip_points, that would change the values. But now a modification of the file is no longer allowed.
A clue in the Suse-documentation made me put the following
settings into the files /etc/powersave/thermal or /etc/powersave/scheme_performance or /etc/powersave/scheme_powersave, respectively:


But this had no effect whatsoever.

Can anybody teach me how to change the trip_points?
Thanks for any help in advance.

But now a modification of the file is no longer allowed.

In my system it is:

-rw-r--r-- 1 root root 0 Jun  9 09:59 trip_points

so root is allowed to write. Or do you mean something different by ‘modification not allowed’?


I also have

-rw-r–r-- 1 root root 0 9. Jun 19:06 trip_points

but when I do (as root)

echo -n “85:0:50:40:35” > trip_points, or try to edit with pico, say,

I get the answer

“Error writing to trip_points: Invalid argument” or “bash: echo: write error: Invalid argument”. Are you able to write this file as root?


Well, all in /proc is not realy a file, so strange things can happen. I only hoped it was that simple as write access for root.

When I try vi on it and try to writ the (unchhanged) file it warns me that it is changed in themean time and asks if I realy waant … I then choose ‘no’ being a bit careful. But it proves there is something there we do not understand fully. And then one should be carefully!

Hope somebody else may jump in this thread.

I also googled around a little bit and to me it seems that you try to do what others do (even in 2007). However nobody mentions its kernel level, so it might have changed.