A friend recently bought a Cyberpower UPS which is showing less than 60 watts for a basic i5 Windows 7 desktop computer at idle plus LCD display. There is no separate video card.
Have others seen very low wattage readings with newer computer systems? It is hard to believe that power consumption could be that low. As a test, a 100 watt light bulb was plugged into the UPS and power did increase by 100 watts. The readings appear to be accurate.
It appears that many new LCD monitors are under 20 watts. Disk drives are apparently quite low also. USB 2.0 supplies a maximum of 2.5 watts which is enough for many backup drives.
That is typical, my cyberpower UPS shows about 70-80w idle, with my server (4670k, mATX motherboard, 4x 2.5" hdd's, no dedicated VGA) and gigabit switch turned on. Plus I also have connected 2 screens and another computer, AV system, speakers, (which are off but draw a little power) and my NAS when idle (disks not spinning).
My core 2 duo rig idles below 80w (that's with a 6570 which should idle for 10w) so it's not too much of a difference for being 7 yrs old. Disk drives haven't changed any, there's really not much they can do to the electric motor.
Thanks all for your replies. It doesn't look like 400-500 watt power supplies are needed in the average PC.
I realize that peak power readings will be higher as disks spin up, the DVD drive is used, CPU usage increases, fans deal with higher temperatures, and complex high speed video is sent to the monitor. But even peak power would not likely be much beyond 2.5X the power at idle.