Power consumption is very important today, with people more aware of the rising costs of living. Adopting a more efficient computer will reduce the cost across a year. That said, someone running an overclocked, overvolted system will not be that concerned with power consumption.
We used a calibrated meter to measure the power at the wall. No monitors were factored into the readings. All systems included the same graphics card, memory configuration and hard drive population.
We measured wattage at the socket when running Cinebench R11.5 64 bit which loads all cores to 100% utilisation. The graphics card was inactive during the reading.
When we overclock the Core i7 3770k to 4.8ghz it demands 230 watts of power at the socket. It drops to around 120 watts when idle.