While idling, Ubuntu 7.10 was consuming the most power with 41 Watts while Fedora 8 Test 3 had consumed the least amount of power at 38 Watts. Both Windows XP and Vista were consuming 39 Watts while idling. As this system was using SiS Real 256 graphics, Compiz Fusion was not enabled by default for Ubuntu 7.10, yet it had consumed the most power. Going back to our previous article, Ubuntu 7.10 does have NetworkManager enabled by default, Tracker, and other background processes. Thanks in part to software optimizations for the One Laptop Per Child (OLPC) project, Fedora has been able to consume less power.
In our "desktop usage" power tests, both Fedora 8 Test 3 and Ubuntu 7.10 had consumed more power than both versions of Microsoft Windows tested. Fedora and Ubuntu were consuming 65 Watts while Windows XP had only consumed 58 Watts and Windows Vista was in the middle with 62 Watts. Granted, this test isn't very controlled and was just intended to give a rough overview.
At Phoronix we'll be publishing more power-oriented articles in the near future, but with the number of requests received for a Windows versus Linux power comparison, we wanted to get these numbers out there. If you have any additional questions, interested in other benchmarks, or would like to share your thoughts, be sure to stop by the Phoronix Forums.