linux-kernel - Re: AMD Quad Core clock problem?

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Date:	Tue, 15 Apr 2008 03:11:20 +0200
From:	Krzysztof Halasa <khc@...waw.pl>
To:	lsorense@...lub.uwaterloo.ca (Lennart Sorensen)
Cc:	"H. Peter Anvin" <hpa@...or.com>, Marc Perkel <mperkel@...oo.com>,
	Chris Snook <csnook@...hat.com>, linux-kernel@...r.kernel.org
Subject: Re: AMD Quad Core clock problem?

lsorense@...lub.uwaterloo.ca (Lennart Sorensen) writes:

> True, but usually they give you an option to turn it off in the BIOS to
> make the system actually work with things like NTP.
>
> Maybe I should have said "Any system with spread spectrum enabled".

I haven't investigated those spread spectrums at all but sometimes
there are options: "center" (the frequency is centered around the
nominal value, I guess) and "below" (or something like that). If done
correctly, "center" shouldn't have visible effect on NTP, should it?

The other important question is "what frequency has spread spectrum
enabled"? CPU (= TSC), HPET, RAM, something else?
-- 
Krzysztof Halasa
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