Battery Life: XP vs Vista

I spent a good deal of time tinkering with my Aspire One over the weekend. I decided to run a non scientific battery life test comparing XP and Vista. The winner gets a permanent spot on my netbook. First, full disclosure about my One. I own the AOA 150 with a 120gig drive w/3 cell battery. I've upgraded the memory to 1.5 gigabytes and recently swapped out the atheros wireless card for an Intel 4965AGN. BIOS version is 3305 which is the latest.

For the purposes of the test I decided to wipe my existing install of Vista Ultimate and install Vista SP1 from scratch. All power settings were left at their defaults and I made sure to visit Windows update to get all available updates before starting the test. Basically, the machine was fully updated and all the internal devices had proper drivers installed. My test was very basic ... open up Firefox 3.03 and browse the web for as long as possible. I achieved a time of 2:02 before the machine put itself into standby.

Next up was XP Home. Rather than use the restore disks I did a clean install making sure to get all available updates from Windows Update. I also made sure that all devices had the latest drivers and that everything was working. The default power scheme was set to "Portable/Laptop." This scheme is similar to the default Vista mode of "Balanced." The key is that when running on battery the operating system will throttle the cpu to half speed, or 800MHz when appropriate. Using the same version of Firefox as well as the same set of bookmarks I was able to achieve 1:59 minutes of browsing time before XP put itself to sleep.

The results surprised me especially because I'd read a good deal on the topic and was expecting around 20% better battery life under XP versus the Aero enabled Vista. I'm basically calling the contest a draw.