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Comment by PragmaticPulp | Hacker News Reader

Not really even close. Even with a 235W CPU and a theoretical 600W GPU you wouldn’t actually exceed even half the capacity of a single 15A circuit in synthetic benchmarks that stress the system beyond real-world loads.

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I think the issue is with older houses that might have 15 amp circuit breakers compared to the modern standard of 20A. One high end desktop computer by itself isn't likely to be a problem, but the way these houses are wired, there are a lot of outlets on the same breaker since they were mostly designed for lighting loads. Our 1950 house in MI will flip the breaker if we use the microwave, toser and bathroom vent at the same time, and my desktop is also on that circuit (with a UPS)

15A vs 20A is a factor of the gauge of the wires as well. You can’t just swap the breaker for a bigger one. You’ll get heat and depending where that could burn the house down.

I have a relative whose house burnt down due to stapled wiring in the attic. Thermal cycling eventually created a short. When your attic catches on fire the smoke alarms go off in time to save the people, but the moment the ceiling starts to cave in the entire house is involved and you’re mostly trying to keep the neighboring houses from burning.

Good callout. Yeah, I should be referring to the electrical circuit as a 15A circuit and not that it's just a limitation of the breaker.

We have the original fabric sheathed wire as well in the walls still which needs to be replaced to modernize the electrical system.

You have a 15A Fuse. You use a 12A Microwave, a 10A Toaster you have blow your breaker right there, and a 10A Bathroom vent?

if you run a separate circut for the Microwave, and separate your bathroom vent + your bathroom LED lights, you can run all of them at the same time with your toster. Running circuts is comparatively easy, vs installing a new 200A fuse box.

If you have bathroom and kitchen on single circuit you have bigger fucking problems than powering gaming PC, whoever did that abomination needs to be fired.

In 1950, that was probably seen as perfectly fine. I used to own a 1942 home that had 4 screw in fuses for the entire house.

For sustained loads you are only supposed to draw 12A, and the PSU has a conversion loss, dropping you to perhaps 10A of power for it all. Plus, then you can’t run anything else on the circuit.

10A is ~1200 watts. That's quite a lot.

It’s easy to go over when you start factoring in other things like monitors etc

A beefy CPU, GPU and a couple of high end monitors can take you to the edge of that and over.

> It’s easy to go over when you start factoring in other things like monitors etc

Why would monitors even be factored in? They shouldn't be on the same circuit anyway.

Why wouldn't they be on the same circuit? The monitor and computer are in the same room and would generally be plugged into the same outlet. I think this would be the rule rather than the exception.

That’s absurd. Most people will not only plug them on the same circuit, they’ll plug everything into a single multi plug feeding from a single wall socket.

I’ve never seen anyone, in corporate and home environments , split their circuit use like you describe.

I would argue most people wouldn't even understand concepts like a circuit.

All they would see is an electrical cable and plug in hand, and an electrical outlet on the wall. Put two and two together, computer turns on. Circuits? Watts? Load? Might as well be pig latin.

253W (13th gen intel) + 450W (video card) + 2 monitors + a speaker system can easily hit 1000W.

Sure, you would be able to put smaller power draw items on the same circuit, but between the CPU/GPU/Motherboard/PSU/Monitors/Peripherals you will not be able to put two of these machines onto the same circuit.

For those confused like me, this conversation is about US circuits. On a typical European 230V 16A circuit, it's not a problem.

Maximum available power for standard domestic users is still only 3kW in many places. Might not be enough for a gaming PC, washing machine and microwave!

You would fit a gaming PC there?

I have a microwave (1270W) and dishwasher (2400W) on the same circuit (230V, 16A). It didn't trip yet...

230 x 16 = 3680 and 1270 + 2400 = 3670. Living on the edge.

Depends on your country, in the Netherlands 25A and 35A main fuses are common.

that's it?? that's not enough to even power an electric stove

Don't forget that they use 230V, and electric stoves often use three-phase power. Even with a 25A fuse that gives almost 10 kW of power.

So do American stoves. I have a 50A/240V circuit for my stove.

Three phase on the other hand is a slight of hand, since that gives you more power than what 230V would imply ;)

Exactly, a "cooking fuse" is not uncommon, which is two 16A lines to the same stove. That gives you 7360W to play with, something you won't reach in practice.

Alternatively, if you already have a multi-phase connection, then you would of course have the lines on different phases. If you have a 3-phase connection 25A main fuse is common, for single phase connections 35A is common.

Just to clarify here: when you talk about a "main fuse", you mean one that sits between the meter and the entire rest of the panel, correct? So individual circuits would be downstream of the main switch.

For context, most American homes have 240V split phase (single phase for all intents and purposes) service with a 200A main breaker.

Wtf do residential homes need 48 kW of power for? I guess it's nice to charge your car quickly, but other than that I'm struggling to think of any uses.

Simultaneously washing and drying clothes while cooking a turkey in the oven, brussel sprouts in the toaster-oven, boiling water for tea, distracting the children with a computer or tv, doing some welding in the garage, and powering a bunch of Christmas lights. --- This is something that actually happened one year. It is much easier to use a big wire and a big breaker/fuse to the house than to have the power go out.

Between my electric heat, dryer, stove, water heater, and car it's easy to get close to the limit, and that's before anything that runs on 120, like computers, a refrigerator, lights, or washer.

Where, in deep russia ?

3kW is typical kitchen power.

In Italy it is very common. The wiring is normally rated for more (4.5kW) The power is limited at the counter switch.

> 3kW is typical kitchen power

Most stoves used to be gas powered. Now induction is becoming more common (but it requires an upgrade to 4.5kW).

A 15A circuit is good for 1440w sustained(120*15*.8), not 1800w.

If you have a circuit in your house that trips for “no reason” this is partially why.

With a steady load you can run a circuit breaker past the rated amperage on the breaker. But look at it funny and it will pop.

The most obvious case of this was when I knew someone who would plug a vacuum into a different circuit and blow a breaker. Just a little noise on the wires and click.

People often use power strips for their computer. So you also have your dual 4K LCD monitor system, as well as maybe plugging in a phone to charge as well which can have high peak power draws over USB 3.0.

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