any thoughts on why cooling fan keeps spinning up and down?

[john wendel]

On 07/05/2009 08:07 AM, Robert L Cochran wrote:
> I think there is probably a physical cause. It gets too easy to blame
> the operating system for physical device issues. The fan speed is
> controlled in part by temperature sensors on the CPU and feedback from
> the fan circuit itself. I think all the fan speed controls are managed
> by motherboard parts, not by the operating system interacting with those
> parts.
>
> Bob
>
>
> On 07/04/2009 08:14 PM, Robert P. J. Day wrote:
>> this is another problem i started having with the test version, and
>> it's still happening now -- on my gateway laptop running fully-updated
>> f11, the cooling fan keeps spinning up and down with about a 3-second
>> period. it's really kind of annoying. occasionally, it will stop
>> completely for a bit, then it starts oscillating all over again.
>> thoughts?
>>
>> rday
>> --


Actually, modern notebooks (and probably most desktops) have their fan 
controlled by the ACPI "thermal zone" driver - strictly software. Saves 
the manufacturers a few cents on every motherboard.

Regards,

John