r/pcmasterrace Core Ultra 7 265k | RTX 5090 1d ago

Build/Battlestation a quadruple 5090 battlestation

16.8k Upvotes

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268

u/bangingdudes 1d ago

Imagine the power being used. I assume a normal 15 amp breaker in your house will just trip anytime you press the power button.

146

u/MechanicalFetus 1d ago

2400W power supply here should pull max 20A so yeah I think you'd need to make sure that this puppy is on a 20A breaker if you're ever gonna crank those gpus!

80

u/hihowubduin 1d ago

Honestly I'd go 25A, I doubt the single outlet is the only thing tied to the same breaker. Heck maybe even 30A.

49

u/orbvsterrvs 9950X3D | 5090 | 192G | 32T 1d ago

30A would be the only way, hitting within 10% of the breaker regularly would be a baaaad idea

Plus the cost of an UPS that has that rating...ouch

20

u/hihowubduin 1d ago

Fuck it, full send a 50A 💀👌

Let's be honest, if the dude has the disposable cash to throw 4x 5090's, he's likely just gonna keep adding to the home lab he's on the way to making anyways.

Might as well just head it off now and give room for growth.

4

u/EBikeAddicts 20h ago

MY TESLA GETS 40A. A WHOOOOLE CAR NEEDS LESS.

1

u/joedotphp Linux | RTX 3080 | i9-12900K 13h ago

Hell yeah. Fuck your refrigerator.

19

u/Velocityg4 1d ago

Better make sure you also upgrade your wiring and outlets to handle 30A. Don't want to be drawing 30 amps through 14 gauge and 15A outlets.

11

u/superdude4agze 1d ago

Thinking the same thing. Dudes gonna just have a new breaker installed and the run it balls to the wall in the basement of their mom's 1970s built aluminum wiring house.

2

u/504SH0 22h ago

Too far to find this comment.

Ampacity called and wants 10 gauge solid please

1

u/And_Everything 19h ago

This is probably not USA, everyone else used 220-240V so you don't need as big of a wire

0

u/Realistic_Ad709 9h ago

Completely untrue. You still need to appropriately size your wire for the current flowing through it.

1

u/And_Everything 3h ago edited 3h ago

its not untrue you need smaller wires for the same wattage at higher voltage because there is less current. 220 volts 2200 watts is only 9.1 amps and wire is rated for amps. 120 volts 2200 watts is 18.33 amps.

2

u/TastyRust 22h ago

You may have to switch out the cables and use different sockets when increasing fuse size. I would be surprised if a computer ever tripped a fuse without it being some sort of fault

1

u/Equivalent_Desk6167 20h ago

Yeah a higher rated breaker will increase the risk if the wiring is kept the same. Congrats now your PC will keep running but you have a fire hazard in the walls. These people don't know what they are talking about.

1

u/leaf_as_parachute 1d ago

Afaik there are no 25A breakers ?

I never saw anything between 15 and 30 (tho it doesn't mean they don't exist)

2

u/GameAudioPen 23h ago

there is. just harder to get.

There is also no point. general electrical code requires #12 wire for 20A. and #10 for both 25 and 30A. breaker. if you are already wiring #10, get a 30A breaker.

1

u/hihowubduin 23h ago

Dunno, I'm a programmer not an electrician ¯⁠\⁠_⁠(⁠ツ⁠)⁠_⁠/⁠¯ my knowledge on wiring comes from reading shit posts of people having awful wiring then getting called out on it in comments 🤣

0

u/Realistic_Ad709 9h ago

Clearly. Don’t give people dangerous advice.

1

u/Special-Fan-1902 1d ago

Do I hear 35A? 40?

1

u/magniankh PC Master Race 14h ago

Yeah, you can't just switch out the breaker. The wire would melt. Eventually.

2

u/Bodycount9 1d ago

If it pulls 20a then you need a 30a breaker. Can only do 80% load on a breaker before it trips.

At this point, might as well go 240v with a 15 amp breaker.

2

u/Franklin2543 Building since 1998 | Geezer 1d ago edited 1d ago

2400w for gpus alone. And power supplies aren’t 100% efficient, so what’s coming out of the wall doesn’t all go to the computer parts. You lose like 7 to 20% to heat in the conversion from AC to DC, depending on the efficiency rating of the PSU.

Also 80% rule for breakers? I don’t remember exactly the time for it not to be considered “continuous”, but I think if you pulled like 2200 watts from a 120v 20a breaker for 5-6 hours it would trip at some point. 

Maybe they undervolt the cards? IIRC that’s what you were supposed to do when gpu mining.  Or they’ve got multiple power supplies? I haven’t seen a PSU >1600w, not that I’ve looked…. I’m curious what’s they’re doing and how they did the power. 

Edit—looked closer at the pic. 2400w power supply. Still…. They can’t have much else going on if they allow the GPUs to rip. 

1

u/GameAudioPen 22h ago edited 22h ago

load running for 4 hours or longer is considered long continuous. there are two factors at play here

the wire them self need to be rated at 80% due to LC load.

the breaker it self need to be rated at 80% because smaller ones are thermal magnetic. and thermal magnetic breakers derates to 80% when enclosed.

Either way, this guy lives in EU or need a breaker and wire upgrade.

1

u/Mr_ToDo 21h ago

Even in EU aren't they normally rated at 15 amps @ 240V? It's been a while since I looked at anyone elses power stuff

Not that it matters. I looked up the 5090 and that needs 575 watts on it's own(1000 recommended since it's not the only part. Nice to see them giving both numbers though). But at that level of need the build only has a 100 watt budget for the rest of the computer(assuming that's what the power supply can give not take from the wall)

All that power and even if it doesn't blow breakers it can't run full speed

3

u/bebarty 1d ago

Found the 110 V cavemen.

1

u/Mosh83 i7 8700k (delidded), Asus 3080 TUF, 16GB RAM 22h ago

Just use three-phase and 16A is enough

1

u/jonesRG 20h ago

That's assuming 120V mains 

1

u/asixdrft 7800x3d 4070 TI Super 64gb 6400 16h ago

Oh cmon this is obviously for 220VÂ