High CPU temperature and high fans level

Arthur Chance freebsd at qeng-ho.org
Sun Jul 17 15:46:42 UTC 2016

On 17/07/2016 13:48, William A. Mahaffey III wrote:
> On 07/17/16 05:05, David Demelier wrote:
>> 2016-07-17 0:25 GMT+02:00 Polytropon <freebsd at edvax.de>:
>>> On Sun, 17 Jul 2016 00:06:07 +0200, David Demelier wrote:
>>>> Hello,
>>>> I was trying FreeBSD 10.3 on my laptop (hp probook 4510s) and was
>>>> surprised
>>>> to see high CPU temperature and fans running high.
>>>> No apps running, I get a temperature of 57C in dev.cpu.x.temperature
>>>> and
>>>> fans run high (not able to get rpms).
>>>> On a 4.6.3 Linux distro I get an average of 48C and fans are quite low.
>>>> Both tests were kept in tty. No Xorg running just a boot and user
>>>> login in
>>>> console.
>>>> Do you have any clue?
>>> Did you enable powerd? It can slow down the CPU when the system
>>> is idle, and increase the CPU speed when needed. This should have
>>> an effect on CPU temperature and fan speed.
>> Yes, I had powerd enabled, I tried -a adaptive, -a hiadaptive as
>> suggested by Erich but it seems that only -a min has some little
>> effect. I could get a temperature of 52C. I've tested back on Linux
>> and I got an average much lower (41C).
>> By the way the other sensors in hw.acpi.tz* are also much higher than
>> Linux (using lm_sensors). The highest value is my tz5 which is at 78C
>> almost 5 seconds after boot while the maximum tz value in Linux
>> sensors is 55.
>> I have no idea what's wrong. :(
> I have had issues w/ FreeBSD apparently not reporting accurate temps on
> this box, AMD jaguar desktop, FreeBSD 9.3R. YMMV & all that rot ....

Ditto. This is a small and old Atom based Zotac system running 10.2:

root at zotac:0# sysctl dev.cpu|grep temperature
dev.cpu.3.temperature: 24.0C
dev.cpu.2.temperature: 24.0C
dev.cpu.1.temperature: 27.0C
dev.cpu.0.temperature: 27.0C

The digital thermometer right next to it is reporting 33.9C in my office
(we're having a hot spell by our standards). There's no way the CPU can
be colder than the ambient temperature.

Moore's Law of Mad Science: Every eighteen months, the minimum IQ
necessary to destroy the world drops by one point.

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