As posted by BeenThere
http://www.extreme.outervision.com/p...ulatorlite.jsp
http://www.corsair.com/psufinder/default.aspx
a couple of the calculators that estimates the size of the PSU needed, and can give clues at the Wattage used for different items.
kill-a-Watt AC wall meters are now 2-3Times cheaper than they were when they first came out, you can get one for ~$20 now. they tell the total AC power being used in watts.
a DMM (Digital Multi Meter) that has a 10 or 20 Amp setting, can be carefully placed (on ONE side) between the wall plug and the wall, to determine the amperage. its not the safest thing in the world, but is another way to determine the power consumption.
just looking up each part that you use , on the web for its specs, and adding it. say you have a 95W processor, and a 123W Gpu, and 4x12 Watt Hard drives, and then add in some losses for conversions, and guess.
and when all else fails, shut off all the curcuit breakers in the location, except the one for the computer, turn off everything that will use power (on that same curcuit), then go out and look at the power meter on the side of the house/apartment .
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