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Why Is Linux Notebook Battery Life Still Poor?
Ganty writes "I recently purchased a Lenovo W500 notebook, and after 'downgrading' to XP and creating a dual partition, I found that I had a battery life of nearly three hours using the long-life battery, at this point I was a happy camper because it means that I can watch a DVD during a flight. I then tried various Linux distributions and found the battery life under FOS to be very disappointing, with an average of 45 minutes before a warning message. After settling on Ubuntu I then spent three days trying various hardware tweaks but I only managed to increase the battery life to one and a half hours. Unwanted services have been disabled, laptop mode has been enabled, the dual core CPU reduces speed when idle and the hard drive spins down when not needed. Obviously Apple with their X86 hardware and BSD based OS have got it right because the MacBooks last for hours, and a stock install of MS Windows XP gives me three hours of life. Why is battery life on notebooks so poor when using Linux? Some have suggested disabling various hardware items such as bluetooth and running the screen at half brightness but XP doesn't require me to do this and still gives a reasonable battery life."
XP's default file system is NTFS, and NTFS is journaled, so I don't think Linux gets an easy out there...
I've personally experienced issues with my laptop BIOS. It works properly in Windows, but a lot of the ACPI functions just flat out don't work in Linux. This is due to a compiler that lets the code compile with errors (Mainly functions that don't return a value when they should). This allows the BIOS programmers to be lazy, and write half assed power functions that don't work properly.
You can fix a lot of these issues by following the instructions in one of the links below to decompile that portion of the BIOS, and recompile it using the Intel compiler. It isn't easy, and certainly isn't something an user should ever have to do. It did fix a lot of the power issues with my HP laptop though (Running hot, not booting on battery power unless a key was pressed, hibernation).
See
http://www.osnews.com/thread?230516
http://ubuntuforums.org/showthread.php?t=1036051
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/272247?comments=all
In this instance, you can blame MS's poor compiler for Linux's poor battery life.
The last time I installed XP on my laptop I had lost some, but not all, of the OEM-supplied driver disks, and it ended up taking me a total of about eighteen hours of solid graft to get it to work. Incidentally, I grew up on Windows, and have only really gotten into FOSS stuff in the last three or four years, and the last time I installed Ubuntu (which took about twenty minutes) it had already configured my screen to the right resolution, got the wi-fi and bluetooth working, got the frickin' bog standard ethernet adapter working, and suggested that I might want to download the right drivers for my GPU by clicking OK and typing my password.
When people say these things, I always have to wonder whether they have ever actually installed Windows. Maybe it's just me, but it takes longer for XP or Vista to simply copy the base installation to the hard drives than it does for me to set up Ubuntu, and I still have to look up which packages I need to install to listen to MP3s or watch DVDs.
Be smart, help people!