News Seasonic's new power supply has enough juice and connectors to power four RTX 4090s

[Admin]

Seasonic has unveiled an all-new 2200-watt flagship power supply with ATX 3.1, PCIe 5.1 support, a 12-year warranty, and four 12V-2x6 power cables.

Seasonic's new power supply has enough juice and connectors to power four RTX 4090s : Read more

 

[DS426]

Going to be a bit of a problem for folks on 120V 15A circuits... (~1800W limit). Heck of a PSU though for sure!

1-2% tolerances are typical almost across the board on Seasonic PSU's.

 

[vanadiel007]

A power supply, or a complete new PS27. Decision decisions...

 

[JamesJones44]

Going to be a bit of a problem for folks on 120V 15A circuits... (~1800W limit). Heck of a PSU though for sure!

1-2% tolerances are typical almost across the board on Seasonic PSU's.

Came here to say the same. Home consumers in North America buying this should make sure to get an electrician lined up to run a 20 Amp circuit for them! Countries in Europe that do 16 amps at 230 should be good to go though.

 

[UnforcedERROR]

Going to be a bit of a problem for folks on 120V 15A circuits... (~1800W limit). Heck of a PSU though for sure!

1-2% tolerances are typical almost across the board on Seasonic PSU's.

I literally thought of this instantly. Good luck if you're a renter!

 

[PlanesFly]

Going to be a bit of a problem for folks on 120V 15A circuits... (~1800W limit). Heck of a PSU though for sure!

1-2% tolerances are typical almost across the board on Seasonic PSU's.

That's incorrect, the sustained load limit for a 120v 15a circuit is only 1,300 watts, you cannot pull 15a continuously. 80% of the circuit limit is your maximum continuous. Don't forget about power conversion losses as well, that further increases the load at the outlet. This 2,200 watt can't even be done on a 20amp outlet, you need 240v circuit .

 

[truerock]

That's incorrect, the sustained load limit for a 120v 15a circuit is only 1,300 watts, you cannot pull 15a continuously. 80% of the circuit limit is your maximum continuous. Don't forget about power conversion losses as well, that further increases the load at the outlet. This 2,200 watt can't even be done on a 20amp outlet, you need 240v circuit .

So. if I bought one of these and plugged it into my 15 amp 120v outlet would it just run and never use the fan?

 

[truerock]

Actually, my APC UPS says I'm getting 122 volts

I wonder how many amps I'm actually getting?

 

[JamesJones44]

That's incorrect, the sustained load limit for a 120v 15a circuit is only 1,300 watts, you cannot pull 15a continuously. 80% of the circuit limit is your maximum continuous. Don't forget about power conversion losses as well, that further increases the load at the outlet. This 2,200 watt can't even be done on a 20amp outlet, you need 240v circuit .

Good point! I didn't even consider sustained circuit output when I was thinking you would need a minimum of 20 amps. 220/240v would be the only option to run it properly.

 

[JamesJones44]

Actually, my APC UPS says I'm getting 122 volts

I wonder how many amps I'm actually getting?

Depends on the circuit and power draw. Most houses in North America run outlets on 15 Amp circuits, but some run 20 Amp circuits for various reasons, typically when they know an area will have a high power draw (garage workshop, counter top kitchen appliances, etc.).

If the unit displays Watts you can convert it Watts / Voltage = Amps used.

 

[folem]

Came here to say the same. Home consumers in North America buying this should make sure to get an electrician lined up to run a 20 Amp circuit for them! Countries in Europe that do 16 amps at 230 should be good to go though.

The good(ish) news is that almost all houses built since the mid-90s should have 20A circuits. The bad news is that those are going to have multiple outlets on a single circuit, usually a whole room and sometimes multiple rooms. I guess you're good as long as you don't turn on anything else in the room while using the PC heavily. Regardless of what the circuit is designed for, most outlets are only designed for 15A - you can tell outlets designed for 20A by the sideways-T shaped neutral slot. The outlet itself isn't a huge deal, a reasonably competent DIYer should be able to swap one in a few minutes with a screwdriver and voltmeter to test that the circuit is actually off (I often use a desk lamp instead).

 

[folem]

So. if I bought one of these and plugged it into my 15 amp 120v outlet would it just run and never use the fan?

It would attempt to run at whatever draw the components in the PC demand plus about 10%. If it ever attempts to draw more than 15A for more than a couple seconds it will trip the circuit breaker and all power will shut off immediately.

 

[folem]

That's incorrect, the sustained load limit for a 120v 15a circuit is only 1,300 watts, you cannot pull 15a continuously. 80% of the circuit limit is your maximum continuous. Don't forget about power conversion losses as well, that further increases the load at the outlet. This 2,200 watt can't even be done on a 20amp outlet, you need 240v circuit .

Sort of. Circuit derating only applies after 3 hours of continuous use. And as of NEC 2002, it only applies in limited circumstances such as if you have cascading or branching circuits or circuits running in insulated walls. It was replaced by new rules that make circuit derating less necessary. Perhaps this has been altered again in NEC 2023 and I'm not aware.

If your home was built before 2002 you should still abide by it. However, it was always intended for commercial settings. 99.9% of people have never even considered reading the NEC and half of those who have won't remember this rule so builders designed homes accordingly. It is not uncommon for people to run 1500-1800W space heaters all day or all night during the winter and houses are not constantly burning down because of it - and when they do it is usually because it fell over, not because it overloaded the wiring).

 

[WonkoTheSaneUK]

A certain other site notes the dual 16-pin GPU connectors on this PSU and claims both will be needed for an RTX5090!

 

[The Historical Fidelity]

So. if I bought one of these and plugged it into my 15 amp 120v outlet would it just run and never use the fan?

Well it would act like a normal PSU if your PC never exceeds the power your PSU can output that corresponds to 1800w input peak or 1300w input constant power usage (IE I mean how much power the PSU takes from the wall, you have to take into account the PSU’s transform loss to figure out how much the PSU can provide your PC before exceeding 15A wall power input). If you try to use it for anything higher then you bought yourself a safety fuse tester as that puppy will do nothing but blow the fuse on whatever 15A circuit you have it plugged into.

 

[The Historical Fidelity]

Sort of. Circuit derating only applies after 3 hours of continuous use. And as of NEC 2002, it only applies in limited circumstances such as if you have cascading or branching circuits or circuits running in insulated walls. It was replaced by new rules that make circuit derating less necessary. Perhaps this has been altered again in NEC 2023 and I'm not aware.

If your home was built before 2002 you should still abide by it. However, it was always intended for commercial settings. 99.9% of people have never even considered reading the NEC and half of those who have won't remember this rule so builders designed homes accordingly. It is not uncommon for people to run 1500-1800W space heaters all day or all night during the winter and houses are not constantly burning down because of it - and when they do it is usually because it fell over, not because it overloaded the wiring).

I specified putting 25A rated 10 awg copper conductors and outlets in all my bedrooms and limit current flow with 15A GFCI/AFCI fuses. The conductor barely heats up after 24 hours of space heater action. It’s absolute overkill but also absolute peace of mind when you are raising a family and have the budget.
Plus, when the children move out, I can switch out one of the room’s fuses for a 25A fuse and boom, I can run my neon’s whenever I want!

 

[Amdlova]

Here in my country has some rules of 10- 20 amp on 127v but no one cares ... in my home got only the breaker on the grid with 60 amps or a 7620w of theorical limit

 

[jp7189]

The good(ish) news is that almost all houses built since the mid-90s should have 20A circuits. The bad news is that those are going to have multiple outlets on a single circuit, usually a whole room and sometimes multiple rooms. I guess you're good as long as you don't turn on anything else in the room while using the PC heavily. Regardless of what the circuit is designed for, most outlets are only designed for 15A - you can tell outlets designed for 20A by the sideways-T shaped neutral slot. The outlet itself isn't a huge deal, a reasonably competent DIYer should be able to swap one in a few minutes with a screwdriver and voltmeter to test that the circuit is actually off (I often use a desk lamp instead).

Not sure if you're referring to North America or not, but in North America, 15A is still the most common run. It's a bad idea to put a 20A outlet at the end of a run designed for 15A, though your breaker will still protect you. Swapping in a 20A breaker and a 20A outlet is a supremely bad idea since the most common line is still 14AWG which isn't rated to handle 20A continously. It may overheat and cause a fire.

 

[YSCCC]

Never understand these psu with power rated to or close to trip your circuit breaker… when I try to build something remotely needing that much power I will reconsider to spec it lower…

 

[Misgar]

the sustained load limit for a 120v 15a circuit is only 1,300 watts, you cannot pull 15a continuously. 80% of the circuit limit is your maximum continuous

That's interesting. Here in the UK, I can plug a 3kW fan heater, fitted with a 13A fused plug into a wall socket and run it for as long as I like. Because we have 30A ring main circuits in our homes, I could plug a second 3kW fan heater into an adjacent 13A socket and heat the room with 6kW. N.B. 3kW at 230V AC = 13A, so 6kW = 26A, well within the capability of a 30A ring main.

If it ever attempts to draw more than 15A for more than a couple seconds it will trip the circuit breaker and all power will shut off immediately.

It's a common misconception that fuses and circuit breakers blow/trip as soon as you exceed their rated current. They will trip virtually instantaneously at very high fault currents many times their rated current, but at currents just above their rating, they will never trip.

If you look at the speed/current curve of a fuse or MCB, you'll see they're unlikely to blow/trip until at least 2 or 3 times the rated current has been flowing for a certain length of time.

In the graph below, a 13A mains fuse (as fitted in a British 13A mains plug) will not blow until 30A flows for 1 second (at the very earliest). The same 13A fuse will not blow even after 10,000 seconds, when the current is 20A (well above the 13A fuse rating). This allows my 3kW heater to draw 13A at 230V all day long. However, if the fault current is 100A, the 13A fuse will blow in one hundreth of a second (very fast).

The plot below shows the speed/time curves for three different types of MCB, types B, C and D. For Type B, the breaker will not trip until at least 3 times the rated current flows for longer than 2 seconds. At 1.5 times rated current, a Type B breaker will not trip until the current has been flowing for at least 40 seconds. So, if a Type B breaker is rated at 15A, it will not trip until 45A (3x15A) flows for 2+seconds. Similarly, the same breaker will not trip at a continuous current of 22.5A (1.5x15A) for 40+seconds.

The practical upshot of this is I might be able to run one of these 2.2kW power supplies with a 10A fuse fitted in a 13A plug. I wouldn't be surprised if the 10A fuse blew, if the switch-on current surge is greater than 100A This seems likely even if an NTC thermistor is fitted in series with the Line input. I look forward to seeing a full test on Tom's Hardware.

 

[husker]

I purchase a power supply never intending to use more than 70% of it's max wattage in order to maintain efficiency (and generally closer to 50% most of the time). Despite the dramatic article headline involving four RTX 4090s, I would hope the purpose of a 2200 watt supply is to allow for a planned max of 1800W without losing efficiency. Should be a good purchase for someone who thinks accordingly.

 

[Misgar]

Ignoring the fact my computer room would turn into a sauna with no AC, I could plug three of these 2,200W PSUs into separate 13A wall sockets in the same room and run them at full power.

Assuming the efficiency doesn't drop below 92% at full rated power, each PSU would consume roughly 2,400W. Therefore three PSUs would consume 7,200W. For this steady-state exercise, I'm completely ignoring the effect of transient current demands made by GPUs such as the RTX 4090, etc.

7,200W divided by 240V (the mains voltage in my house) equals 30A, which is the rating of a standard UK household ring main. Job done! No need to switch the central heating on in winter. Mind you, summer is going to be unbearable, on those few days/weeks when the temperature exceeds 30C.

 

[The Historical Fidelity]

Ignoring the fact my computer room would turn into a sauna with no AC, I could plug three of these 2,200W PSUs into separate 13A wall sockets in the same room and run them at full power.

Assuming the efficiency doesn't drop below 92% at full rated power, each PSU would consume roughly 2,400W. Therefore three PSUs would consume 7,200W. For this steady-state exercise, I'm completely ignoring the effect of transient current demands made by GPUs such as the RTX 4090, etc.

7,200W divided by 240V (the mains voltage in my house) equals 30A, which is the rating of a standard UK household ring main. Job done! No need to switch the central heating on in winter. Mind you, summer is going to be unbearable, on those few days/weeks when the temperature exceeds 30C.

Wow, that’s not a lot of total power y’all are given. Standard in the U.S. is 120V * 100A = 12KW with the average being 150A = 18KW.

 

[Misgar]

Wow, that’s not a lot of total power y’all are given.

Perhaps you were thinking the only power I have is the 7.2kW ring main I was talking about. These 30A ring mains connect a string of 13A UK wall sockets in a chain, on one floor of a house. Each 13A outlet is effectively wired back to the main distribution board via two 2.5mm sq, "twin and earth" cables, hence the 30A overall rating. Ring mains are only used for plug-in appliances up to 3kW each, such as portable fan heaters, washing machines, fridges, computers, TVs, desk lights, etc.

On a 30A ring main, I could power three of these 2.2kW Seasonic PSUs simultaneously in one room. Each PSU would pull 10A (2.4kW) max. The problem would be getting rid of the 7.2kW of heat dissipated in the computer room.

You might need to run additional power lines into your home computer room in the States, to obtain 60A at 120V (7.2kW), if you were mad enough to run three 2.2kW Seasonics. Over here, we'd just plug the three 2.2kW PSUs into separate 13A wall outlets in the same room. Job done.

The mains voltage over this side of the Atlantic is double that usually found in American homes, so it's easy to pull double the power out of the wall for the same current. In the UK the mains voltage is typically 240V 50Hz, in Continental Europe it's closer to 220V.

My house comes with two 100A main circuit breakers in the distribution unit. One of the 100A breakers powers two 30A ring mains (one downstairs, the other upstairs) making 60A. In addition, this first 100A breaker feeds all the lighting circuits in the house (2 x 5A).

The second 100A breaker in my house feeds spurs (as opposed to ring mains) to power heavy duty items like my cooker and a couple of 3.5kW immersion heaters.

If you have power hungry block storage heaters, you'll probably need a third 100A main breaker. With a 7kW+ charger for an electric vehicle, there's a vague chance you might need a fourth 100A breaker and a separate meter for cheap night rate.

Each 100A main breaker can supply 24kW at 240V. I have two 100A breakers so I could (theoretically) pull up to 48kW at 240V.

Three 100A breakers would be 72kW max and four 100A breakers 96kW max, although it's highly unlikely you'd get anywhere near that power draw. The house would probably burst into flames.

Of course we pay through the nose for our power. I think I'm paying the equivalent of US $0.33 per kiloWatthour, so things aren't all rosy over here. My annual electricity bill is close to $1500 with gas central heating payments another $1000 on top. I look at tales of people paying $0.12 per kWhr over in the States with envy.

Mind you, most British homes don't have (or need) AC, so that's one large bill we don't pay. AC is still a luxury item in most homes, not a "must have". We just put up with the odd day when the temperature exceeds 95F (35C) and switch on a desk fan. Summers are mild, with occasional hot spells, winters are cool, but not bitingly cold. Shops, banks, server rooms and many offices have AC though.

 

[The Historical Fidelity]

Perhaps you were thinking the only power I have is the 7.2kW ring main I was talking about. These 30A ring mains connect a string of 13A UK wall sockets in a chain, on one floor of a house. Each 13A outlet is effectively wired back to the main distribution board via two 2.5mm sq, "twin and earth" cables, hence the 30A overall rating. Ring mains are only used for plug-in appliances up to 3kW each, such as portable fan heaters, washing machines, fridges, computers, TVs, desk lights, etc.

On a 30A ring main, I could power three of these 2.2kW Seasonic PSUs simultaneously in one room. Each PSU would pull 10A (2.4kW) max. The problem would be getting rid of the 7.2kW of heat dissipated in the computer room.

You might need to run additional power lines into your home computer room in the States, to obtain 60A at 120V (7.2kW), if you were mad enough to run three 2.2kW Seasonics. Over here, we'd just plug the three 2.2kW PSUs into separate 13A wall outlets in the same room. Job done.

The mains voltage over this side of the Atlantic is double that usually found in American homes, so it's easy to pull double the power out of the wall for the same current. In the UK the mains voltage is typically 240V 50Hz, in Continental Europe it's closer to 220V.

My house comes with two 100A main circuit breakers in the distribution unit. One of the 100A breakers powers two 30A ring mains (one downstairs, the other upstairs) making 60A. In addition, this first 100A breaker feeds all the lighting circuits in the house (2 x 5A).

The second 100A breaker in my house feeds spurs (as opposed to ring mains) to power heavy duty items like my cooker and a couple of 3.5kW immersion heaters.

If you have power hungry block storage heaters, you'll probably need a third 100A main breaker. With a 7kW+ charger for an electric vehicle, there's a vague chance you might need a fourth 100A breaker and a separate meter for cheap night rate.

Each 100A main breaker can supply 24kW at 240V. I have two 100A breakers so I could (theoretically) pull up to 48kW at 240V.

Three 100A breakers would be 72kW max and four 100A breakers 96kW max, although it's highly unlikely you'd get anywhere near that power draw. The house would probably burst into flames.

Of course we pay through the nose for our power. I think I'm paying the equivalent of US $0.33 per kiloWatthour, so things aren't all rosy over here. My annual electricity bill is close to $1500 with gas central heating payments another $1000 on top. I look at tales of people paying $0.12 per kWhr over in the States with envy.

Mind you, most British homes don't have (or need) AC, so that's one large bill we don't pay. AC is still a luxury item in most homes, not a "must have". We just put up with the odd day when the temperature exceeds 95F (35C) and switch on a desk fan. Summers are mild, with occasional hot spells, winters are cool, but not bitingly cold. Shops, banks, server rooms and many offices have AC though.

Thank you for explaining! That sounds much more reasonable. My home is setup with a 400 amp main breaker box with an additional 200 amp breaker for my garage and outdoor power (mainly to cover the EV fast charger, power tools, and landscape lighting). And appliances in the US like Ovens, stove tops, clothes dryers, large fridges and freezers are generally run on 220-240V power. So it’s not like we are stuck with just 120V power, just we differentiate the voltage for high and low power use cases. After all, the great electrification of the U.S. was spurred by Edison and his light bulb and we kept his original voltage ever since.

And you are quite right about A/C as a luxury in the UK, but down here in Texas, it’s akin to a God-Given Right since we have to endure 40-46C (105-115F) for months at a time.