Date: Thu, 29 Jan 2009 12:08:59 -0500
From: Dave Jones <davej@redhat.com>
To: Xiaoning Ding <dingxn@ymail.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: a question about p4_clockmod module on Xeon quad core
	processors
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	Xiaoning Ding <dingxn@ymail.com>, linux-kernel@vger.kernel.org
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On Thu, Jan 29, 2009 at 08:32:41AM -0800, Xiaoning Ding wrote:

 > >  > Thanks for the correction. 
 > >  > My experiments need to reduce CPU speed. However, I
 > > can only reduce the speed by about 30% (from 2.67GHz to
 > > 2GHz) with ACPI. That is not enough for the experiments. 
 > > 
 > > The ACPI P-states are nearly always correct, so you
 > > won't be
 > > able to go below 2GHz on this system.
 > 
 > That's true for changing P-States with ACPI. But I can still get slower speed with clock modulation, right?

Clock modulation will lower the performance, but the clock speed
will remain constant.

	Dave

-- 
http://www.codemonkey.org.uk
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