On Tue, Aug 19, 2008 at 3:42 AM, Andi Kleen <andi@xxxxxxxxxxxxxx> wrote: > "Vedran Rodic" <vrodic@xxxxxxxxx> writes: >> >> Windows power monitoring tool from Lenovo reports power usage of 6.5 W under >> the same LCD brightness level and with wireless disabled. > > It would be better if you compared using the same "neutral" method. > > Most cheap power measurements tend to quite inaccurate and who > knows in which direction this Windows power monitoring tool is wrong. > It might be wrong in a different direction than what you used > under Linux. Yeah, or they might not be wrong and my eyes could be :( It turns out that Windows can get the LCD brightness down more than thinkpad-acpi, or whatever is turning down the brightnes when I press the Fn-End combination (both in X and in the console - I guess it's the BIOS). > > A reasonable accurate method might be to just measure the time how > long the battery lasts in both cases using a similar workload > (e.g. keeping it completely idle) Difference between lowest Windows LCD brightness levels and Linux brightness levels: 3:40h on Windows (it hibernated the laptop when the battery was arround 5% percent, did arround 10 more minutes sitting on the grub screen). 2:36 on Linux. Now the question is how do I get the LCD brightness down even more on X, but this may already be solved in the latest Xorg intel driver, just not with the Fn keys. If I see any more surprising battery life differences when I manage to get the same low brightness level on both OS-es, I'll let you know. Vedran -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
