From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arjan van de Ven Subject: Re: [Discuss] Speedstep on Celeron SU2300 - 20% more battery lifetime on Windows Date: Mon, 06 Sep 2010 08:47:28 -0700 Message-ID: <4C850D10.2050801@linux.intel.com> References: <201009020152.37466.trenn@suse.de> <201009061035.03727.trenn@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <201009061035.03727.trenn@suse.de> Sender: cpufreq-owner@vger.kernel.org To: Thomas Renninger Cc: Tiago Marques , discuss@lesswatts.org, linux-pm@lists.linux-foundation.org, cpufreq@vger.kernel.org, linux-acpi@vger.kernel.org List-Id: linux-acpi@vger.kernel.org On 9/6/2010 1:35 AM, Thomas Renninger wrote: > Hi, > > I am adding lesswatts.org and linux-pm list. > I expect you found out why you do not get frequency/P- states and it > seem to be correct. On these lists, people can help you further > to find out Linux vs Windows battery drain differences. > > If you have the same backlight settings, I expect C-state or graphics > card must be the reason. There is nothing else than CPU or GPU > that drains so much energy for being the reason of > 20% more battery life time. > Which graphics card and driver do you use (for nvidia/ati, trying the > binary one for comparison, might show a big difference on a recent > card)? > Which C-state driver do you use (there is an acpi and intel_idle one > with latest kernels): > cat /sys/devices/system/cpu/cpuidle/current_driver > I hope to be able to provide a c-state tool soon, for now you have to > go through: > cat /sys/devices/system/cpu/cpu*/cpuidle/state* > to check which and how often/efficient C-states are used. powertop will tell you exactly this (and the next version will provide much much more detail)