Here is our current test system.

For idle testing we waited 5 minutes into start up from Windows Vista Ultimate SP1 and measured the power draw. The load was tested using 3DMark 2006.

Against the much more expensive Antec the Tarantula does well and as we can see most users will never use that much power but with losses from efficiency and degradation of parts over time it's good to have more power necessary than to be right on the edge.