Thinkpad T61 - Fan running a lot of time

Thinkpad T61 - Fan running a lot of time

[Renato S. Yamane]

Hi,

Anyone have seen fan turned-on in 90% of the time?

I see that fan power-on when processor is up than 45°C and power-off 
when is under 45°C.

Temperature difference between 2 cores is 5°C in idle (Core1=45°C and 
Core2=40°C)

Local temperature is ~25°C, kpowersave is in "dynamic mode", my 2 cores 
(Intel T7500) is running 94% of the time in idle (checked with "top"), 
with clock in 800MHz.

The fan speed is ~2600RPM (always under 3000RPM), and I think that is 
not enough to cooling the processor, because is necessary 3min to 
decrease 1°C in Core1 and only 40sec to increase 1°C.

I think that is necessary a higher fan speed.

I see this in Debian Lenny (2.6.26-1) and 2.6.28.8 kernel... Maybe in 
other versions too.

Regards,
Renato

Re: Thinkpad T61 - Fan running a lot of time

[Henrique de Moraes Holschuh]

On Tue, 24 Mar 2009, Renato S. Yamane wrote:
> The fan speed is ~2600RPM (always under 3000RPM), and I think that is  
> not enough to cooling the processor, because is necessary 3min to  
> decrease 1°C in Core1 and only 40sec to increase 1°C.
>
> I think that is necessary a higher fan speed.

Or a better thermal coupling between the fan assembly and the
processor...  this is a weak area on thinkpads.

If your box is still under warranty, I suggest you to use
thinkpad-acpi fan control to keep your fan at level 7 (fastest normal
fan level).  If that's not enough, call in for a motherboard
replacement.

-- 
  "One disk to rule them all, One disk to find them. One disk to bring
  them all and in the darkness grind them. In the Land of Redmond
  where the shadows lie." -- The Silicon Valley Tarot
  Henrique Holschuh

Re: Thinkpad T61 - Fan running a lot of time

[Renato S. Yamane]

Henrique de Moraes Holschuh wrote:
> Renato S. Yamane wrote:
>> The fan speed is ~2600RPM (always under 3000RPM), and I think that is
>> not enough to cooling the processor, because is necessary 3min to
>> decrease 1°C in Core1 and only 40sec to increase 1°C.
>>
>> I think that is necessary a higher fan speed.
>
> Or a better thermal coupling between the fan assembly and the
> processor...  this is a weak area on thinkpads.
>
> If your box is still under warranty, I suggest you to use
> thinkpad-acpi fan control to keep your fan at level 7 (fastest normal
> fan level).  If that's not enough, call in for a motherboard
> replacement.

Updated BIOS to 7LETC5WW (2.25) and...

Fan speed is stabilished in ~3000RPM, temperature go to 42°C and fan 
speed still power-on.

# cat /proc/acpi/ibm/fan
status:         enabled
speed:          3028
level:          auto

# echo level 7 > /proc/acpi/ibm/fan
bash: echo: write error: Invalid argument

How can I change fan level?

Regards,
Renato

Re: Thinkpad T61 - Fan running a lot of time

[Henrique de Moraes Holschuh]

On Tue, 24 Mar 2009, Renato S. Yamane wrote:
> # echo level 7 > /proc/acpi/ibm/fan
> bash: echo: write error: Invalid argument
>
> How can I change fan level?

Read the driver documentation, at Documentation/laptops/thinkpad-acpi.txt.
Fan control is locked by default, for hardware safety reasons.  The docs
tell you why, how to use the fan control interface, and how to unlock it.

Also, I suggest you get used to the hwmon fan control interface on /sys,
procfs is going away sooner or later...

-- 
  "One disk to rule them all, One disk to find them. One disk to bring
  them all and in the darkness grind them. In the Land of Redmond
  where the shadows lie." -- The Silicon Valley Tarot
  Henrique Holschuh