After looking at some of the draws of the typical desktop computer system I am confused by power supply ratings which seem to be excessive.
The big item in a desktop computer, the CPU typically has a peak load of around 50W. Heavy duty CD-ROM burners can be 30W and the typical HDD or other device is around 10-15W max. All told, if everything in a computer is going full blast it is sucking down maybe 250W - 300W at the outside.
Nevertheless, the computer power supplies typically sold are touted as 500W, 600W, even 800W devices. This does not seem to make much sense unless these are the input wattage of the power supply. Since there is a lot of heat loss, to deliver 250W of regulated power, you might need as much as 500W inbound.
So, is that the way these power supplies are marketed? By reporting the input power consumption, not the output wattage?
If so, that would seem to be very deceptive because the input power is irrelevant. What is important is how much regulated power the supply generates. After all, who wants a 2000-Watt power supply if it can only generate 100W of regulated power?