With our second test we looked at the different system sensors for a two minute period during which we again started off with a clean desktop and then proceeded to launch each of the desktop's default file manager followed by launching the default web browser and just navigating through each of the desktop's different menus and other basic tasks. This is to represent light usage on each of the KDE/GNOME/LXDE/Xfce desktops.
Now when looking at the battery consumption for this second test the numbers are more intriguing than the battery-power-usage test profile results. KDE 4.4.1 ended up consuming the most amount of power during this test with an average rate of 14.1 Watts while LXDE did the best at 12.9 Watts, or a 9% reduction in the power drain. GNOME 2.29.1 was second best in terms of consuming the least amount of power with an average of 13.1 Watts while Xfce was slightly behind at 13.3 Watts.
The results from the system memory usage monitoring are similar to our first test run. LXDE continued to go through the least amount of system RAM while KDE used up the most and in between was Xfce and then GNOME.
When looking at the system temperature, the power-hungry KDE 4.4.1 Software Compilation was the only desktop where the system temperature varied different from the rest. The average system temperature as monitored through ACPI with Phodevi was 48°C for KDE and 45~46°C for GNOME, LXDE, and Xfce.
Run these tests for yourself using the Phoronix Test Suite. We are also working to design a new class of desktop environment benchmarks looking at other areas, if you have any feedback or suggestions let us know via the forums.