Power Supply's pulling serious power

[UptheMiddle]

Love reading through the technical forums as people are always sharing a tremendous amount of knowledge.

So, perhaps this question has an easy answer: Recent computer builds require people to put in heavy duty power supplies (like 700 - 1000Watts!). Yet, I haven't heard much regarding concerns for home wiring. Pulling a 1000W through 14 gauge wiring PLUS other appliances/lights probably isn't a good idea. Typically, a 14gauge home circuit has a network of lights and plugs on it (say two bedrooms and a hallway, perhaps up to 6 light bulbs and 9 outlets). Such a plan assumes lighter appliances/electronics being used without all sockets being used at once (hence power limitation). But, take one outlet and pull 1000Watts through it PLUS the lights and other outlets, may have a condition where the wire diameter and insulation aren't enough.

What's the bottom line, then? Dedicated 20Amp circuit with 12AWG?

 

[DaveSimmons]

The problem isn't as bad as you think.

People are buying 1,000 watt PSUs, but the computer is then only drawing 500 watts for 2x 800 GTX in SLI.

A system with a single 8800 GTX draws less that 350 watts under max load according to a DailyTech kill-a-watt measurement.

 

[Paperdoc]

You are right to raise the question. However, it gets tricky right away because a 700W PSU normally does NOT consume 700W, because it is not actually supplying its max output to the computer most of the time.

Still, I look at my system with multiple outlets and power bars. There's a computer with its PSU input. Then a printer, powered speakers, cable modem, router, powered USB hub, monitor, VCR for video work, video camera recharger, external HDD power supply, and a couple work lamps. Many of these are small power consumers, but the total starts to look like 750 to 1000 watts easily. You really don't want that on a circuit with other lighting and home entertainment stuff drawing power, too.

About all one could do is borrow a current meter (or ask an electrician friend to help) and actually measure the pwer consumptions. Then you'd know for sure whether a separate circuit is needed, or maybe just a re-arrangement of where things plug in.

 

[yh125d]

The power running through a wire is nothing to be worried about. The power(watts) of a standard home circuit is the voltage(120v) x amperage(8amps) = 960watts. the limitations of a certain size of wire isnt how much power it can take, it is how much amperage it can take.


(edit) also, the wiring of a house doesn't consist ov just one circuit, each breaker in your circuit box is a different circuit, each running @ 120v/8a/960w.

(edit2)The way a PSU works, besides converting AC to DC, is conerting the 120v/8a input into 3.3, 5, and 12v outputs, for the sake of this example, we'll just assume there is only one 12v output. The 120v input is reduced to 12v, which pushes the amperage up to a maximum of 80 amps. but psu's do not put out 80 amps, most is either used by the 3.3 and 5v channels, or is choked by the added resistance of the psu, which is why the psu gets hot, some of that choked amperage is converted to thermal energy