I tested my Asus EeePC 1001P battery today – I turned off the screensaver and fully charged the battery and then left it running with the screen on and downloading a website. It got to just over 7 hours before the battery had 5mins left in it, so I’d say the realistic battery life is 7.5 hours of average use not 11 – still its better than I thought.

There are a few powersaving features in Fedora – the screen dims when the keyboard/trackpad are not in use, the wireless card has a powersaving mode when there are no packets going through, the CPU underclocks to 1GHz, the webcam is disabled when not in use, the harddisk spins down and the screen can turn off instead of just going to screensaver, or you can even set it to sleep the PC entirely.

What I like the most is that when you plug in the AC power, it goes back to full 1.66GHz and undims the screen etc.

I’m going to have another go with Jupiter tomorrow as apparently without it Linux isn’t using the SHE system (FSB/GPU underclocking) and all possible power saving modes like disabling USB and VGA-out when not in use. Also SHE can overclock the CPU/GPU/FSB when running on AC power.

I’ve not tested it, but still Windows XP seems to report longer battery life when full.

Update: I’ve installed Jupiter and the eeepc-support utilities and have added the following to the kernel line in /boot/grub/menu.lst

acpi_osi="!Windows 2009"

I also blacklisted the eeepc_wmi module in /etc/modprobe.d/ so that the old eeepc_laptop module is loaded which has SHE support in sysfs.

Apparently this won’t be needed in Fedora 15 with its 2.6.37 kernel and newer eeepc_wmi module.

Jupiter has a mechanism for running scripts when switching to battery or AC power, so I’ve added the following two scripts to /usr/lib/jupiter/vendors/ASUSTeK Computer INC./ that turn powersaving on/off for the ath9k wireless card.

power:

#!/bin/bash
/sbin/iwconfig wlan0 power off

battery:

#!/bin/bash
/sbin/iwconfig wlan0 power on

Update 2: with all the above settings I managed to get 8.5 hours from a full charge, apparently with kernel 2.6.37 as in Fuduntu 14 or Fedora Rawhide, it should manage the 11 as advertised.