Yea, that's true, but even so, the powerful ATX PSU still consume nearly the same power as room heater (6 to 12 Amps, depending on the wattage of DC rails), and I decided to set Cool 'n' Quiet so that way it can go from 10 Amps on 12V CPU plug to 3 Amps when idling. It's not so much when surfing Internet, but playing game or do benchmarking would be a whole different story. On Dell PSU, at 115 Volts AC, the current draw sits at 10 - 11.5~ Amps. The Active PFC ATX PSU with microcontroller (or microprocessor) inverter subsystem/driver, they would consume much lesser power - still I would put it nearly same league as their older, inefficient cousin.