Ubuntu 8.04 vs. Windows Vista Power Usage
 

In Q4'07 we had looked at Ubuntu's power consumption with all of their Linux releases going back to Ubuntu 5.04. While Linux has improved in recent years when it comes to power efficiency and optimizations, more processes running on the desktop had canceled out any real power improvements. Following that article was a look at power consumption between Windows and Linux. We had used an old desktop system in that comparison and Ubuntu 7.10 was consuming the most power while idling but Fedora 8 Test 3 had consumed the least amount of power and had beat out both Windows XP and Vista. While using the desktop, however, both versions of Windows had consumed less power than Fedora and Ubuntu. With Ubuntu 8.04 LTS now available, we have decided to run another simple power comparison. This time we are using a Lenovo ThinkPad notebook and an AMD server as we see whether Ubuntu Hardy Heron or Microsoft Windows Vista consumes less power

http://www.phoronix.com/vr.php?view=12278

let me guess, Vista with Aero uses more...