Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932704AbWBYMyW (ORCPT ); Sat, 25 Feb 2006 07:54:22 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932705AbWBYMyW (ORCPT ); Sat, 25 Feb 2006 07:54:22 -0500 Received: from allen.werkleitz.de ([80.190.251.108]:17804 "EHLO allen.werkleitz.de") by vger.kernel.org with ESMTP id S932704AbWBYMyV (ORCPT ); Sat, 25 Feb 2006 07:54:21 -0500 Date: Sat, 25 Feb 2006 13:53:37 +0100 From: Johannes Stezenbach To: Dave Jones , Adrian Bunk , Dmitry Torokhov , davej@codemonkey.org.uk, Zwane Mwaikambo , Samuel Masham , Jan Engelhardt , linux-kernel@vger.kernel.org, Andrew Morton , cpufreq@lists.linux.org.uk, ak@suse.de Message-ID: <20060225125337.GB8698@linuxtv.org> Mail-Followup-To: Johannes Stezenbach , Dave Jones , Adrian Bunk , Dmitry Torokhov , davej@codemonkey.org.uk, Zwane Mwaikambo , Samuel Masham , Jan Engelhardt , linux-kernel@vger.kernel.org, Andrew Morton , cpufreq@lists.linux.org.uk, ak@suse.de References: <20060214152218.GI10701@stusta.de> <20060222024438.GI20204@MAIL.13thfloor.at> <20060222031001.GC4661@stusta.de> <200602212220.05642.dtor_core@ameritech.net> <20060223195937.GA5087@stusta.de> <20060223204110.GE6213@redhat.com> <20060225015722.GC8132@linuxtv.org> <20060225042456.GA7851@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060225042456.GA7851@redhat.com> User-Agent: Mutt/1.5.11+cvs20060126 X-SA-Exim-Connect-IP: 84.189.211.213 Subject: Re: Status of X86_P4_CLOCKMOD? X-SA-Exim-Version: 4.2 (built Thu, 16 Feb 2006 12:49:04 +1100) X-SA-Exim-Scanned: Yes (on allen.werkleitz.de) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1448 Lines: 34 On Fri, Feb 24, 2006, Dave Jones wrote: > On Sat, Feb 25, 2006 at 02:57:22AM +0100, Johannes Stezenbach wrote: > > On Thu, Feb 23, 2006, Dave Jones wrote: > > > On Thu, Feb 23, 2006 at 08:59:37PM +0100, Adrian Bunk wrote: > > > > And if the option is mostly useless, what is it good for? > > > > > > It's sometimes useful in cases where the target CPU doesn't have any better > > > option (Speedstep/Powernow). The big misconception is that it > > > somehow saves power & increases battery life. Not so. > > > All it does is 'not do work so often'. The upside of this is > > > that in some situations, we generate less heat this way. > > > > Doesn't less heat imply less power consumption? > > Not really. The only energy you're saving is that your CPU fan > will turn slightly slower, which is probably going to be < 1W > of difference. I thought the fan turns slower because the CPU generates less heat, which in turn is because it consumes less electrical energy. If someone has done measurements I'd be interested to know the numbers about the actual power savings which can be achieved by using P4 clock mod. I don't expect it to be much, but I bet it's more than 1W. Johannes - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/