We measured the power consumption with the system resting at the Windows 7 desktop, representing idle values.
The power consumption of our entire test system is measured at the wall while loading only the CPU using Prime95′s Small FFTs setting. The rest of the system’s components were operating in their idle states, hence the increased power consumption values (in comparison to the idle figures) are largely related to the load on the CPU and motherboard power delivery components.
With its host of add-on controllers and overclocking-orientated design, Asus’ Rampage IV Black Edition draws over 10% more power than MSI’s basic X79A-GD45 Plus. Even when the CPU is overclocked and loaded, power consumption remains below 350W, though.
Needless to say, the Asus Rampage IV Black Edition’s target audience is unlikely to be concerned by the board’s power consumption; two or more graphics cards will dwarf the motherboard’s energy usage numbers.