Re: How does one control fans?

["H.S." <hs.samix@gmail.com>]

Koen Vermeer wrote:

> If your system is really running too hot (more so than when running XP),
> look at what process is taking CPU time. Or maybe you aren't using
> throttling, so the CPU is always running at full speed? In that case,
> enable CPU frequency scaling and make sure it runs with the right
> governor (probably 'conservative').
> 
> Otherwise, maybe the thermal trip points are too low. Look
> at /proc/acpi/thermal_zone/THRM/temperature to determine the temperature
> according to the system. Then look
> at /proc/acpi/thermal_zone/THRM/trip_points to see the trip points. In
> my case, it shows something like
> 
> critical (S5):	100 C
> passive:	92 C: blabla
> active[0]:	66 C: blabla
> active[1]:	63 C: blabla
> 
> This means that at 63 degrees, the fan (FAN1) starts blowing, at 66
> degrees FAN0 also starts, at 92 degrees the system is throttled, and at
> 100 degrees it's turned off. Also, my current temperature is 42 degrees,
> and the fans are indeed turned off.
> 
> For more information, look at
> http://acpi.sourceforge.net/documentation/thermal.html
> 
> Koen
> 
> 

I am using cpufreqd and it helps quite a bit, but my fan is still noisy
and as the OP it is ON even when the laptop is not noticably hot.

I have:
$> cat cooling_mode
<setting not supported>
cooling mode:   critical
$> cat trip_points
critical (S5):           90 C

That 90C was 88C before I tried this command:
/proc/acpi/thermal_zone/THM# echo 90:0:70:0:0 > trip_points

So this command did not give different trip points, only the critical
value was changed.

How do I set the cooling mode and/or the trip points?

->HS