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Date: Sun, 18 Jan 2004 23:55:06 +0100 (MET)
From: Adriaan de Groot <adridg@sci.kun.nl>
To: "David O'Brien" <obrien@FreeBSD.ORG>
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cc: freebsd-amd64@FreeBSD.ORG
Subject: Re: CPU throttling
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On Sun, 18 Jan 2004, David O'Brien wrote:
> On Wed, Jan 14, 2004 at 03:41:16PM -0600, James Van Artsdalen wrote:
> > Is CPU throttling possible with AMD64?
>
> Nope.  We don't have a Cool&Quiet PowerNOW driver.

I had C&Q turned on in the BIOS of my Asus k8v, and coupled with the
zalman 7000cu cooler, the behavior was as follows:

0) at boot, spin fan at 2500rpm for 5min
1) shut off fan entirely (damn frightening!)
2) wait for CPU temp. to reach 50 degrees
3) switch on fan at 2500rpm
4) wait for CPU temp. to reach 30 degrees
5) goto 1

it actually worked reasonably well, and the lockups i experienced every
other day could just as easily have been panics as overheating :) i
haven't tried it recently, though.

-- 
 Adriaan de Groot    adridg@cs.kun.nl     Kamer A6020     024-3652272
GPG Key Fingerprint 934E 31AA 80A7 723F 54F9  50ED 76AC EE01 FEA2 A3FE
               http://www.cs.kun.nl/~adridg/research/