So if W=V*A...

[Melbosa]

I can see issues with Gaming boxes say in locations like a lan party or Frag with the new 1000w power supplies coming.

If Watts = Volts X Amps, then Amps = Watts / Volts.

Code Select Expand


1000w
------  =  9.09091amps
110v


Given that power supplies aren't a 100% efficient, adding roughly 10% for this, roughly 10amps required per 1000w power supply to supply close to 1000w.  Given that a Quad Core system, with average 3 fans a case, 2 HDs, and 2 Vids (Granted not everyone will be that high end), according to online watt calculators for systems, this requires about 900w of power.  So basically 2 of these guys in 1 circuit, with decent system load, may be the whole 15amp circuit or may even be too much for a 15amp circuit (don't forget you need USB device power and Monitors yet).

[Mr. Analog]

You are correct:
1 amp = 1 watts/1 volts
1 amp = 10 watts/10 volts

While I think it is a fair assumption that most power supplies do not use 100% of the specified Wattage, that connecting multiple power supplies up to the same circuit would be a risk. I think it would be safest to calculate draw as a maximum.

Planning a LAN party somewhere?

[Melbosa]

Invited to one, and getting my new system.  Seems 2 of us will be running high rigs, and mine according to Antec's power consumption calculator will draw 909w of power.  So I figure with my LCD, USB Keyboard and Mouse, I should be running about 9 amps or so.

[Melbosa]

Also was thinking for Frag this may become a bigger issue next year as well.

[Lazybones]

Purchase one of those plug-in power meters like I did, it will tell you your peak, average and total power use.

[Cova]

On one hand - if a system was actually drawing 1000W of power from a 1000W PSU, it would draw more than the 9ish amps due to inefficiency (10A is prolly a safe bet)

On the other hand - the chances of the CPU(s), GPU(s), HD(s), etc. all drawing maximum current at the same time is very slim.  If you put your new system on a power-meter I would bet it draws in the 5-6A range while under load.  Only one way to confirm that though.

[Melbosa]

Yeah.  We will see.  More people coming to this lan party than last year, and higher end rigs.  Just was doing some checking to make sure.

On a positive note, my place is so easy to add another electrical outlet to the living room, that I'm going to get a buddy of mine to run a new circuit for my TV and PC setup as I have an AC unit in the living room during the summer, and might have issues with a single 15A circuit.

[Lazybones]

The one thing that seems to be a problem with the new 1000W units, is that when you turn them on there is a momentary spike that trips some GFI breakers.

[Tom]

Depending on the psu, It'll have a much lower efficiency, as low as 75%-80%, especially when pulling close to max or max wattage. IIRC A great PSU will have 90-95% efficiency in ideal conditions (draw isn't too low, or too high), where as many sit around 80% at best. See HardOCP for an indepth review of several 500w PSUs.

On a positive note, my place is so easy to add another electrical outlet to the living room, that I'm going to get a buddy of mine to run a new circuit for my TV and PC setup as I have an AC unit in the living room during the summer, and might have issues with a single 15A circuit

Yeah, I need a new one in my living room too. Networking gear, 3 computers, a TV, couple lights and a 800W window AC. I was blowing the circuit often enough till I moved my main PC off to the kitchen circuit. (good thing too now that I have two 21" CRTs, a C2Q and a 8800GTS sucking down the juice).

Yup, running 2 Athlon 2ghz boxes, 1 1Ghz athlon box, Cable modem, 8 port switch, Linksys PAP2 VOIP adapter, occasionally a Dlink Wifi Router, My TV, two Pole lamps and an AC unit on the same 15a circuit.

The one thing that seems to be a problem with the new 1000W units, is that when you turn them on there is a momentary spike that trips some GFI breakers.

Initial power up probably pulls so much current that it'll trip almost anything. Have you seen the size of the Capacitors and other components in PSUs these days?

[Adams]

It's not GFI but Arc Fault Circuit Interrupteurs (AFCI)

All AFCI breakers see the power spike as a similar wave length to a Arc Fault... which trips it. It is a general flaw in the breaker design it self. I had a 600 Watt power supply and it would trip the breaker no mater what I did. You can get around some of the issues with getting a Power supply that does not have the built in power arc protection... or what ever they call it. It is hard to find power supplies with out it.

I believe Druid found one since his would pop every time he turned on his computer.

Anyways thats just what I found out from reading and scouring the internet. I would say an older house wouldn't have to worry about that because they do not have AFCI breakers but most have some GFI and those do not cause any issues.