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To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Lennart Sorensen <lsorense@csclub.uwaterloo.ca>,
       Marc Perkel <mperkel@yahoo.com>, Chris Snook <csnook@redhat.com>,
       linux-kernel@vger.kernel.org
Subject: Re: AMD Quad Core clock problem?
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From: Krzysztof Halasa <khc@pm.waw.pl>
Date: Tue, 15 Apr 2008 03:45:38 +0200
In-Reply-To: <480403DE.4070901@zytor.com> (H. Peter Anvin's message of "Mon\, 14 Apr 2008 18\:24\:46 -0700")
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"H. Peter Anvin" <hpa@zytor.com> writes:

> It shouldn't really matter, since "below" produces a similar spectrum
> at a slightly lower frequency.

Sure for CPU/TSC and similar clocks but in case of well-known (not
calibrated) frequency it could be a problem. Not sure if there are
such cases.

I wonder if spread spectrum could affect calibration of (various)
timers - unlike NTP calibration is a short process.
-- 
Krzysztof Halasa