InfoWorld debunked five PC power related myths on its blog. Here's one of them:
Myth No. 1: The power used turning my PC on negates any benefits of turning it off. Forrester debunks this myth as follows: The average desktop draws 89 watts per hour. If it's left on overnight for 16 hours, it consumes 1.42kW. It's impossible for the power surge that occurs when powering on a PC to rival that figure: "You would be drawing energy at a rate of 17 kWh -- the equivalent of 44 HP DL580 servers at 100 percent utilization. Moreover, the average US wall outlet can only provide 1.8 kW of draw, which is about one-tenth of what the power surge would require."