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Date: Thu, 02 Jan 1997 20:06:31 -0600
To: Michael Smith <msmith@atrad.adelaide.edu.au>
From: Tony Overfield <tony@dell.com>
Subject: Re: CPU fan detection...
Cc: freebsd-hackers@freefall.freebsd.org
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At 11:48 AM 1/3/97 +1030, Michael Smith wrote:
>Just to change the subject slightly...
>
>The Intel CPUs with integrated fans do indeed have a fan sensor of some
>sort.  Anyone know how to read it?  It'd make for a good idle-loop
>check...

The Intel 486->Pentium Overdrive CPU, with the integrated fan, will disable 
the internal clock multiplier when the fan stops.  You could check to see 
if your 100 MHz CPU suddenly seems to be running at only 33 MHz.