Management of Thermal

Norberto Meijome freebsd at meijome.net
Wed Oct 10 16:26:02 PDT 2007


On Wed, 10 Oct 2007 14:59:05 +0200
Mel <fbsd.mobile at rachie.is-a-geek.net> wrote:

> Experience with a HP laptop shows this to be not true. It currently is working 
> perfectly with a laptop cooling pad and not going anywhere near critical 
> values, but before that, we had to use the following in /etc/sysctl.conf to 
> prevent the computer from locking up (I suspect that the Intel CPU shuts 
> itself down before burning out):
> hw.acpi.thermal.user_override=1
> hw.acpi.thermal.tz0._PSV="75C"
> hw.acpi.thermal.tz0._CRT="80C"
> 
> These values are 5C lower then detected values. I started with 10C lower and 
> reached critical too early. 5C works perfectly. Logging the temp[1] each 
> minute I could see the effect of the cooling fans once it reached 75C.

Hi Mel,
from man acpi_thermal
     hw.acpi.thermal.tz%d._PSV
             Temperature to start passive cooling by throttling down CPU, etc.
             This value can be overridden by the user.

which implies is at what temperature it'll use methods other than the fans to cool down.

Your experience seems to contradict this (*._PSV = temperature at which fans kick in)  ?
thanks,
B

_________________________
{Beto|Norberto|Numard} Meijome

"Outside of a dog, a book is man's best friend. 
 Inside of a dog, it's too dark to read."
  Groucho Marx

I speak for myself, not my employer. Contents may be hot. Slippery when wet. Reading disclaimers makes you go blind. Writing them is worse. You have been Warned.


More information about the freebsd-mobile mailing list