Anyone running a 4090 on sub 1KW PSU?

WilyKit

Gawd
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Per subject line, anyone? Issues? 4090 on its way and currently running a 850watt Seasonic. I do plan on setting power limit to 60-70% since it appears to have a negligible performance impact but quite a large power impact. Based on some reviews it should pull roughly the same power as a 3080Ti which is marginally thirstier than my current 3080. Seems transient spikes are also far better controlled on 40 series cards than 30 series.

At some point I will get around to upgrading PSU but ATX 3.0/PCIe 5 PSU's are still few and far between and the new Seasonic Vertex units that just popped up on Newegg are all back ordered.
 
You'd have to research the specs of your PSU. Manufacturers have anywhere from 1.2x rated power to as high as 1.5-1.6x for tripping OPP protection. And this is assuming the product is working to spec--there is always going to be some variance.

I find the easiest way to trip power protection circuits is to rapidly alt-tab out of a game at full load to desktop and back. If your PSU can survive a dozen of those cycles in rapid succession, it should probably be able to handle any transient spikes. That's always my goto PSU stress tester with GPUs.
 
I'm on a 1050W gold but I can't run my cpu and Gpu at 100% that would be maxing out the PS. So I have the GPU at 55% and the CPU 100W and it's running perfect no issues whatsoever probably even better to run in eco mode honestly but then until my backordered MSI Meg Ai1300W Platinum ATX3.0 PS comes through till next week and I install it I'll crank up everything to the max 🤠
 
I'm on a 1050W gold but I can't run my cpu and Gpu at 100% that would be maxing out the PS. So I have the GPU at 55% and the CPU 100W and it's running perfect no issues whatsoever probably even better to run in eco mode honestly but then until my backordered MSI Meg Ai1300W Platinum ATX3.0 PS comes through till next week and I install it I'll crank up everything to the max 🤠
Have you tried running them at 100% or assuming it wouldn’t handle the load? Lots of people over estimate power usage, transient spikes aside.
 
Corsair SF750, no issues and I overclock, overvolt and raise the powertarget to 133%. The rest of my rig is low power though since it is an mITX build.
 
Corsair SF750, no issues and I overclock, overvolt and raise the powertarget to 133%. The rest of my rig is low power though since it is an mITX build.
A 4090 in an otherwise low power build? What is the point? I cant imagine a CPU in that build being remotely suitable for a 4090 considering even the fastest CPUs made cant fully push it in every game. To me it just sounds like you are bottlenecking a 4090 to the point where of course your PSU is not an issue snice its not even being pushed.
 
A 4090 in an otherwise low power build? What is the point? I cant imagine a CPU in that build being remotely suitable for a 4090 considering even the fastest CPUs made cant fully push it in every game. To me it just sounds like you are bottlenecking a 4090 to the point where of course your PSU is not an issue snice its not even being pushed.
An over-clocked, over volted and raised power target 4090 no less.

But good to know a 750 was able to handle it
 
An over-clocked, over volted and raised power target 4090 no less.

But good to know a 750 was able to handle it
I do not think you understand. If he has a cpu that is too weak to push a 4090 then the 4090 is not being anywhere fully utilized anyway. Raising the power target and overclocking means nothing if the card was not even reaching its stock power limits.
 
I do not think you understand. If he has a cpu that is too weak to push a 4090 then the 4090 is not being anywhere fully utilized anyway. Raising the power target and overclocking means nothing if the card was not even reaching its stock power limits.
A small ITX system with a 4090Ti would be like a midget with a 16" dong
 
I do not think you understand. If he has a cpu that is too weak to push a 4090 then the 4090 is not being anywhere fully utilized anyway. Raising the power target and overclocking means nothing if the card was not even reaching its stock power limits.
no I get it. I’m agreeing with you. im Pointing out that it’s even more unbalanced than it seems with the way he has it tuned. He has it over volted so it’s just wasting power even while not hitting power limits.
 
I'm running my RTX 4090 on a 1000w PSU just fine. Both CPU and GPU are overclocked and not a single hiccup, restart or issue since launch day for the RTX 4090. My CPU draws quite a bit more power than the OP here and my system is 100% stable at 5500Mhz all core for the CPU with 1.3v and the card running with a 108% power target (520w) with the core set to a +100 offset and the memory to +500.

The OP here should be fine with an 850w PSU considering his CPU draws far less power than my 13700K. He shouldn't need to limit the card to only 60-70% power target.
 
I'm running my RTX 4090 on a 1000w PSU just fine. Both CPU and GPU are overclocked and not a single hiccup, restart or issue since launch day for the RTX 4090. My CPU draws quite a bit more power than the OP here and my system is 100% stable at 5500Mhz all core for the CPU with 1.3v and the card running with a 108% power target (520w) with the core set to a +100 offset and the memory to +500.

The OP here should be fine with an 850w PSU considering his CPU draws far less power than my 13700K. He shouldn't need to limit the card to only 60-70% power target.
How much power (W) does your 13700k cpu pull at 5500MHz at 1.3?

Also which connector are you using to pull 520W on the 4090?
 
The question OP is trying to have answered is whether or not a person with an average or greater modern motherboard and CPU has been run with an RTX 4090, on a PSU that's 850 watts, or 750 watts. OP wants to know real world, tried and tested experiences. Answers based on hypothesis, as well as answers regarding odd-ball systems that modify the normal power usage, are likely not what OP is looking for.

I'd like to see more people who have actually tested a modern, typical high-end system with a sub-1000w PSU and an RTX 4090 answer OP.
 
A 4090 in an otherwise low power build? What is the point? I cant imagine a CPU in that build being remotely suitable for a 4090 considering even the fastest CPUs made cant fully push it in every game. To me it just sounds like you are bottlenecking a 4090 to the point where of course your PSU is not an issue snice its not even being pushed.
I mean in general the mITX boards use about 20-40 less watts than full ATX and only have two sticks of RAM. I also have a 5800X3D which is lower power than what Intel offers. I probably should have worded that better, I didn't mean low power like Energy Star Compliant office PC. Just low power for a high end gaming rig.
 
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I mean in general the mITX boards use about 20-40 less watts than full ATX and only have two sticks of RAM. I also have a 5800X3D which is lower power than what Intel offers. I probably should have worded that better, I didn't mean low power like Energy Star Compliant office PC. Just low power for a high end gaming rig.

Oh, just that sort of thing? I was imagining downclocked everything, but GPU cranked way up, to make a dark joke of CPU bottleneck on the RTX 4090.

Which is already a bit of a benevolent problem. The moment you get past that initial CPU/RAM/Mobo/PSU bottleneck, I'm sure the RTX 4090 is a true demon. However, an mITX build does not at all imply "slower" nor "lower wattage usage." It's merely a form factor, and therefore, as long as you give it the electrical juice it craves, it'll most certainly burn bright on even the coldest nights. Praise be to Nvidia and also AMD.

In any case, it's good to know if a 4090 can be safely handled on our pre-RTX 4000 PSUs. For me, I have an expensive as heck ROG Thor 850 watt, and I only bought it because I truly believe in the ROG philosophy and live its truth each day. I also noticed that it's just a high-binned Seasonic PSU, and there's nothing wrong with that. With the amusing features and the promise of a long-life, I got it.

But then the RTX 4090 came out.

I sure hope my old high-end PSU can run an RTX 4090, because once I save up enough $$$$$$ I'll certainly want to get the 4090. But it's just SO much money that to have to buy a new PSU as well, is a dark and harrowing thought. Raw visceral fear at the thought of somehow trying to sell this ROG Thor which is totally a gimmick brand, and can't really be resold as anything than a generic PSU, in terms of the used market. Just to buy some other gimmick brand of PSU, to ensure my computer is being powered by the best components. So it'd just be more and more money being shoveled into the pit of nVidious fire as I try to buy overly high-end computer parts, just so my rig is fully juiced.

In any case, if the mITX board can be cooled, then it'll run at full CPU and RAM specifications, and cooling is just reliant on having the right cooling solution. For mITX, I imagine a mostly open-air watercooling setup, to keep the rig sealed in radiators, to emphasize the extremely small size and ensure it doesn't require a bigger case just to fit the monstrous RTX 4090 GPU. No, it'd have to be perfectly tight and watercooled, so the cooling can be moved elsewhere, away from the actual motherboard, which should be displayed as if an art piece.

That's just my idealistic mITX fantasy though. I'm sure you do something interesting with your mITX system. Have you done any additional power testing and benchmarking?
 
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That's just my idealistic mITX fantasy though. I'm sure you do something interesting with your mITX system. Have you done any additional power testing and benchmarking?

The highest I've seen pull around 720W (Kill-a-Watt reading) from the wall with everything maxed out in Metro Exodus Enhanced at Max Settings at 4K, GPU at maximum limits. Games like CP2077 will pull around 620W

Here's what it's capible of on 3DMark:
https://www.3dmark.com/3dm/87672969
https://www.3dmark.com/sw/302956
 
Which PS or power connector? Total system or we talking GPU?
That's from the wall so total system power. I use the CableMod 3x8 Pin connector with my SF750.
Your score is 29985.

Don't you think you should do what it takes to get to 30000?
It's a lot of effort to break 30K with a 5800X3D. My chip is kind of average as well so it makes it harder, out of the box it only boosted to 4.2GHz. Now I have it boosting to 4.4GHz all core.
 
Was running 13600k and 4090 (both slightly overclocked + 3x NVME, 3x hard drives and custom loop) with tx850m. The only reason I upgraded to rm1000x was to lower my noise as max power usage at wall was around ~620 W (so around 550 W by all components before PSU efficiency loses). Not a single crash. I definitely wouldn't worry about running 4090 on quality 850W power supply and the only legitimate reason for upgrade could be either a) noise b) higher PSU efficiency (running PSU above 60% capacity lowers efficiency somewhat).
 
How much power (W) does your 13700k cpu pull at 5500MHz at 1.3?

Also which connector are you using to pull 520W on the 4090?
The CPU will draw about 275w at full tilt and I’m using the native 16pin connector that came with my PSU.
 
I ran mine on a system with a quality 750W unit with no issues. It was a 6700K/Z170 rig though so not as power hungry as top of the line current chips.
 
I ran mine on a system with a quality 750W unit with no issues. It was a 6700K/Z170 rig though so not as power hungry as top of the line current chips.
So you upgraded to a better CPU now? That was an absolutely massive waste of what a 4090 can do with that CPU. You're talking laughable levels of performance down the drain to where the point of even a 4080 with a newer CPU would have crapped all over that 4090 with that CPU you had.
 
So you upgraded to a better CPU now? That was an absolutely massive waste of what a 4090 can do with that CPU. You're talking laughable levels of performance down the drain to where the point of even a 4080 with a newer CPU would have crapped all over that 4090 with that CPU you had.

Whoosa my man, relax. It was my friends rig and I was having a hard time getting his 1070 to display on my monitor (I found out later it was the DP firmware) and I grabbed the first card that wasn't installed in something to make sure his rig could get to windows (it couldn't cuz it had a bad drive). I ended up benching it in there some just out of curiosity.
 
Running the Seasonic Focus platinum 850W with 4090/5800x3D. Full load the system pulls ~550w. No concerns.
 
I also run a 750w PSU with my 4090, it's a super flower leadex titanium, so it is pretty high quality. One thing to remember about the 4090 is that it has less transient power spikes compared to the 3090 so it's actually a bit easier overall on the power supply.
 
Ran my SFFPC setup with a 3090 before and had to get my SF750 replaced. Running a 1000w outside my case right now waiting on the new SFX PSUs with the new connector for the 4090.
 
I also run a 750w PSU with my 4090, it's a super flower leadex titanium, so it is pretty high quality. One thing to remember about the 4090 is that it has less transient power spikes compared to the 3090 so it's actually a bit easier overall on the power supply.
Than the plain 3090? Not according to techpowerup as the 4090 had higher spikes than the 3090. And really even the 3090 TI only had about 30 Watts higher spikes than the 4090 in their review which is less than 6% difference.

https://www.techpowerup.com/review/nvidia-geforce-rtx-4090-founders-edition/39.html
 
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It really depends on the rest of the system. If you're running a 4090 + i9 13900KS, you're pushing it pretty hard. A 1000-watt PSU would probably be a good choice.

I'm running my 4090 with a Ryzen 5800X3D, which is incredibly power efficient. I've never seen my system go above 700-watts usage even under extreme load.
 
It really depends on the rest of the system. If you're running a 4090 + i9 13900KS, you're pushing it pretty hard. A 1000-watt PSU would probably be a good choice.

I'm running my 4090 with a Ryzen 5800X3D, which is incredibly power efficient. I've never seen my system go above 700-watts usage even under extreme load.
The 13900KS can pull close to 400 and the 4090 with a 600W power can pull over 500? Even if they both pull 75% of their max isn't that cutting it close for a 1000w?
 
The 13900KS can pull close to 400 and the 4090 with a 600W power can pull over 500? Even if they both pull 75% of their max isn't that cutting it close for a 1000w?
Good point.

This is the reason full system power draw is so important nowadays. Intel's highest CPUs are power hogs, while the 5800x3D, which is still one of the best gaming CPUs you can buy and a very able companion to an RTX 4090, sips power by comparison.
 
I used my 4090 with my Corsair AX850 for about 5 hours of gaming and 2 of office work before the 4090 fried itself and my motherboard during a firmware update of the 4090 RGB controller. The power supply did survive however and I am still using it. I was using an overclocked I7-3770K. Using a i74770K with same power supply with no issue. The replacement 4090 I was sent is still in the box until I can replace the case/mobo etc…
 
I used my 4090 with my Corsair AX850 for about 5 hours of gaming and 2 of office work before the 4090 fried itself and my motherboard during a firmware update of the 4090 RGB controller. The power supply did survive however and I am still using it. I was using an overclocked I7-3770K. Using a i74770K with same power supply with no issue. The replacement 4090 I was sent is still in the box until I can replace the case/mobo etc…
Why are you using a 4090 with such outdated CPUs? A GPU like that with a 3770k or 4770k is just beyond stupid and a massive laughable waste of a $1,600 GPU.
 
Why are you using a 4090 with such outdated CPUs? A GPU like that with a 3770k or 4770k is just beyond stupid and a massive laughable waste of a $1,600 GPU.
Well at the time I decided it was time to upgrade the 4090s were very hard to obtain so the first chance I had to order the exact model I wanted I did. I swore to myself I would wait for reviews of all 4 phases of CPU releases before picking what I wanted (raptor lake/zen4/raptor lake 6 GHZ/3d cache.) In the meantime I figured why not use the 4090 since my 1080 was running at 99% utilization for the only game I played.
 
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