I see. Thanks. It seems that intel_idle isn't supported on Core 2 based Celerons. Best regards > On Tue, Sep 7, 2010 at 12:28 AM, Arjan van de Ven <arjan@xxxxxxxxxxxxxxx> > wrote: >> >> ÂOn 9/6/2010 3:03 PM, Tiago Marques wrote: >>> >>> On Mon, Sep 6, 2010 at 4:47 PM, Arjan van de Ven<arjan@xxxxxxxxxxxxxxx> >>> Âwrote: >>>> >>>> ÂOn 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 >>>> >>> Thank you. Please see my previous e-mail. C0, C1 and C4. Do you know >>> of any way to force the intermediate ones for debugging? >> >> intel_idle driver is the only way that's reasonable in amount of work. >> >> for anything else you depend on the grace of the bios. >> > > -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html