[Pkg-acpi-devel] Bug#500809: laptop overheating

Jack Bates ms419 at freezone.co.uk
Wed Oct 1 16:28:04 UTC 2008

Package: acpi
Version: 1.2-1
Severity: normal

My Lenovo 3000 N100 recently started regularly overheating. It does not
actually power off, but it slows to a crawl and feels hot to touch. There is
even a faint smell of "hot components".

First, I tried checking the temperature:

ket% cat /proc/acpi/thermal_zone/TZ00/temperature
temperature:             88 C

I also checked the processor "throttling":

ket% cat /proc/acpi/processor/CPU0/throttling    
state count:             8
active state:            T7
state available: T0 to T7
    T0:                  100%
    T1:                  88%
    T2:                  75%
    T3:                  63%
    T4:                  50%
    T5:                  38%
    T6:                  25%
   *T7:                  13%

I guess this explains why the laptop slows to a crawl.

Next I checked the thermal zone "state":

ket% cat /proc/acpi/thermal_zone/TZ00/state 
state:                   passive

Now, it seems to me that when the laptop is this hot, it should be in "active"
cooling mode. I see this output from "cooling_mode":

ket% cat /proc/acpi/thermal_zone/TZ00/cooling_mode
0 - Active; 1 - Passive

So I tried:

ket:~# echo 0 > /proc/acpi/thermal_zone/TZ00/cooling_mode 

However the state remains "passive" and no fans come on, etc.

Finally, this is the output from "trip_points":

ket% cat /proc/acpi/thermal_zone/TZ00/trip_points
critical (S5):           102 C
passive:                 87 C: tc1=0 tc2=4 tsp=4 devices=CPU0 CPU1 

How can I keep my laptop from overheating?

-- System Information:
Debian Release: lenny/sid
  APT prefers unstable
  APT policy: (500, 'unstable')
Architecture: i386 (i686)

Kernel: Linux 2.6.26-1-686 (SMP w/2 CPU cores)
Locale: LANG=en_CA.UTF-8, LC_CTYPE=en_CA.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/bash

Versions of packages acpi depends on:
ii  libc6                         2.7-13     GNU C Library: Shared libraries

acpi recommends no packages.

acpi suggests no packages.

-- no debconf information

More information about the Pkg-acpi-devel mailing list