Detecting CPU throttling on over temperature

Daniel O'Connor doconnor at
Wed Sep 9 00:48:15 UTC 2009

On Wed, 9 Sep 2009, Alexander Motin wrote:
> Daniel O'Connor wrote:
> > I recently discovered a system where the floppy drive cable was
> > intermittently fouling the CPU fan - I believe this caused the CPU
> > to overheat and then get throttled by the BIOS.
> >
> > Does anyone know if it is possible to determine if this is the
> > case? ie is there a way to be informed if throttling has occurred?
> Theoretically it is possible. I know off-topic tool reporting this.
> Also you can just monitor CPU temperature, depending on CPU type.

Monitoring CPU temperature is a bit difficult, there are a lack of tools 
(although I have some code it's not complete).

The problem is that the CPU temperature is only a proxy measurement, I 
would much prefer to be told directly the BIOS is throttling rather 
than guess :)

Daniel O'Connor software and network engineer
for Genesis Software -
"The nice thing about standards is that there
are so many of them to choose from."
  -- Andrew Tanenbaum
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