From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wes Felter Subject: Re: Status of X86_P4_CLOCKMOD? Date: Mon, 27 Feb 2006 15:17:37 -0600 Message-ID: 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> <20060225125337.GB8698@linuxtv.org> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20060225125337.GB8698@linuxtv.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: linux-kernel@vger.kernel.org Cc: cpufreq@lists.linux.org.uk Johannes Stezenbach wrote: > 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. Clock modulation can reduce power by 40W on a 3.6GHz Xeon when the system is running a high-power application (e.g. Linpack). (It also reduces performance by a factor of 6-10). Clock modulation saves no power at all during idle. Wes Felter - wesley@felter.org