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RTX 3080 power supply requirements - 850W?

DRDOOM

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I've had a look at the following website where several PSUs were texted with the RTX 3080, and it appears the peak load can be very high.

The recommendations of this tester were 850W for the RTX 3080.

Thoughts?

Here is also the peak power load from Igor's Lab
j8uUYny.jpg
 
I've had a look at the following website where several PSUs were texted with the RTX 3080, and it appears the peak load can be very high.
Igor in Germany his is the only reliable source so far for making electrical measurements over PC hardware.
The measuring setup this worth over 10000 Euro.
But only one qualifying electronic engineer he may interpret correctly the measurement results.
10 to 20ms this translates to frequent power requirement.
The scaling at lower milliseconds this translates to less frequent power requirements.

The most important discovery that Igor confirmed this is that PCI-E slot this deliver up to 5.5A.
All the other energy this is supplied due the dual 6+2P.

NVIDIA did add an active power limiter on their cards, this translates that even if you get a 2000W PSU, the card will never use it.


Thoughts?
You need to learn German language and become also an electronics engineer.
 
A new quality 650 will do.
Tho considering prices between 650/750 variants tend to be rather small, its best to go with a 750 (if were talking a small 10-15$ diff).
 
techspot was pulling around 525w peak off their test rig so I would say a 850w would not be "overkill" if you were in the market for a new PSU. If you already have a very good 650w or solid 750w then I don't think you would not necessarily need a new unit (unless noise was becoming a factor).
 
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Just undervolt it.
 
Igor in Germany his is the only reliable source so far for making electrical measurements over PC hardware.
The measuring setup this worth over 10000 Euro.
But only one qualifying electronic engineer he may interpret correctly the measurement results.
10 to 20ms this translates to frequent power requirement.
The scaling at lower milliseconds this translates to less frequent power requirements.

The most important discovery that Igor confirmed this is that PCI-E slot this deliver up to 5.5A.
All the other energy this is supplied due the dual 6+2P.

NVIDIA did add an active power limiter on their cards, this translates that even if you get a 2000W PSU, the card will never use it.



You need to learn German language and become also an electronics engineer.
Nvidia recommend a 850 watt power supply, do you believe people plucked that figure out their asses?.
It's overkill possibly, but if the PSU is not single rail and it's lower than 850 it's possible that one or more of the supply rails to the pciex is not capable of supplying enough current.
 
Unless you have a really crappy PSU, I would not worry about sub-ms power spikes or the 850W stated requirement.
Smoothed and averaged over 10-20 ms, card stays in its power limit. Shorter spikes are just the nature of power delivery here.
850W is stated while also accounting for crappy PSUs that overstate their capabilities. Noname 900W may or may not actually be capable of that. Less common these days but you never know.

If my memory serves right, Igor also measured some 5700XT cards pulling 400+W in sub-ms :)
I am very certain that Radeon VII and 200+W Turings also get these 400+W spikes there.

techspot was pulling around 525w peak off their test rig so I would say a 850w would not be "overkill" if you were in the market for a new PSU. If you already have a very good 650w or solid 750w then I don't think you would necessarily need a new unit (unless noise was becoming a factor).
While you are correct, it is worth noting that Techspot's rig runs a 3950X. And they also measured the card itself - it was pulling 327W.
 
Nvidia recommend a 850 watt power supply, do you believe people plucked that figure out their asses?.
It's overkill possibly, but if the PSU is not single rail and it's lower than 850 it's possible that one or more of the supply rails to the pciex is not capable of supplying enough current.

No I do believe the opposite that NVIDIA plucked that figure out their ass....
They seem to perform calculations based on SLI cards when them Killed SLI due drivers just yesterday.
 
No I do believe the opposite that NVIDIA plucked that figure out their asses.
Kind of. But it is an educated guess and has been done in similar way for a long while.
RTX3080 pulls 350W. High-end CPU pulls 200W, probably 250W if an Intel CPU. Some 50W for other stuff. Then add 30% just to be safe :)

Edit:
Did not actually calculate anything but looks like this guess was a closer than I expected:
350 + 250 + 50 = 650W * 1,3 = 845W
:D
 
No I do believe the opposite that NVIDIA plucked that figure out their asses.
While you're entitled to your opinion, I wager the engineering department of Nvidia don't use guess work.
You realise that misleading the public on electrical requirements could lead to time in court.
Plus over the years, gaming, folding and mining I have met the limitations of every power supply I have owned at some point, normally while theoretically well within it's limits, and operating specs, because work loads on GPU'S especially, due to min max current load swing's, can make for transient spikes that shut down a PSU, not guesswork, been there many times.
 
While you're entitled to your opinion, I wager the engineering department of Nvidia don't use guess work.
You realise that misleading the public on electrical requirements could lead to time in court.
NVIDIA does not make laws, all that they offer this is multiple recommendations, not even a single one, so them to take responsibility about it.
Look the chart again.
There is no red line limits.
 
NVIDIA does not make laws, all that they offer this is multiple recommendations, not even a single one, so them to take responsibility about it.
Look the chart again.
There is no red line limits.
No they're ruled by them duhh, they don't build your pc, they recommend specs but if you're under specs pile doesn't work or pops , it's not on them if you made it.
 
No they're ruled by them duhh, they don't build your pc, they recommend specs but if you're under specs pile doesn't work or pops , it's not on them if you made it.
All true, but there is a golden recommendation if you plan to get old with your new GPU, if your PSU this is now out of warranty then buy a fresh and keep the old as spare.

Edit:
Did not actually calculate anything but looks like this guess was a closer than I expected:
350 + 250 + 50 = 650W * 1,3 = 845W
:D

Well here is some Greek style teaching , no free fish, but of how to learn to get one by your self.
Corsair CX750 W (the good made version), this deliver 1150Watt before protection activates.
Now calculate the headroom from 750W up to 1150W by you offering to us this value as percentage.
 
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While you're entitled to your opinion, I wager the engineering department of Nvidia don't use guess work.
You realise that misleading the public on electrical requirements could lead to time in court.
Plus over the years, gaming, folding and mining I have met the limitations of every power supply I have owned at some point, normally while theoretically well within it's limits, and operating specs, because work loads on GPU'S especially, due to min max current load swing's, can make for transient spikes that shut down a PSU, not guesswork, been there many times.

Who is gonna sue nVidia for recommending PSU with a bit more wattage than is realistically needed?

Other way round is MUCH more likely - they recommend PSU cutting it close, so some average uninformed Joe buys PSU of dubious quality that meets the wattage recommendation. But since it's dubious quality, it fails, possibly damaging card itself. Average Joe is uninformed so he sues nVidia for making "false" recommendation.

I.e., nVidia has incentive to make recommendation higher than what is really needed. And sure enough, over the years people were able to run setups containing specific cards with PSUs of lower wattages than officially recommended - without any issues.

Recommending higher wattage PSU than needed is not even a lie of any kind - it is recommendation, not a hard statement that this card won't run on lower wattage PSU. Then again if you can afford newest RTX in current times with scalpers/miners/whatever other BS going on, then you're surely not gonna have a problem with paying up a little for a little higher wattage model in reputable series.

FWIW FCPowerup test lists several 650W units as passing, so this is lowest number known to work with RTX, as long as PSU is of respective quality (listed were Seasonic and Super Flower units).
 
Who is gonna sue nVidia for recommending PSU with a bit more wattage than is realistically needed?

Other way round is MUCH more likely - they recommend PSU cutting it close, so some average uninformed Joe buys PSU of dubious quality that meets the wattage recommendation. But since it's dubious quality, it fails, possibly damaging card itself. Average Joe is uninformed so he sues nVidia for making "false" recommendation.

I.e., nVidia has incentive to make recommendation higher than what is really needed. It's not even lie of any kind - it is recommendation, not a hard statement that this card won't run on lower wattage PSU. Then again if you can afford newest RTX in current times with scalpers/miners/whatever other BS going on, then you're surely not gonna have a problem with paying up a little for a little higher wattage model in reputable series.

FWIW FCPowerup test lists several 650W units as passing, so this is lowest number known to work with RTX, as long as PSU is of respective quality (listed were Seasonic and Super Flower units).
How did you get that from what I said, Nvidia are legally bound to correctly disclose the power use and requirements of their technology.

They spec higher because of the reasons you quote and more I agree.

I never said someone would sue for quoting too high a PSU requirement any where, just that Nvidia like us all Are bound by laws.
 
While you are correct, it is worth noting that Techspot's rig runs a 3950X. And they also measured the card itself - it was pulling 327W.

Like I said, if you have a very good 650w unit it will work as the 525w figure was a peak number not a constant pull. Obviously with a system that draws less power than techspot's test rig, the individual's power requirements will be lower.
 
PSUs last much longer and are less prone to failure if you are not using them close to their maximum rated wattage not to mention the fan noise that some exhibit when under a lot of load. So while a good lower wattage PSU "may do just fine", it's not optimal.
 
Like I said, if you have a very good 650w unit it will work as the 525w figure was a peak number not a constant pull. Obviously with a system that draws less power than techspot's test rig, the individual's power requirements will be lower.
Spot on.

Too many hyoerconservatives here for sure..lol.

For theast 2o years I've bought psus where the stress test load is no more than 80% of the psu's limit. Through dozens of builds for myself and clients I never ran these at 50%. So while it is true that they last longer... if you get a quality lsu with a 7-10 year warranty like you should in the first place, you dont need to overspend on additional wattage because of some convoluted idea in people's heads about running at 50% or something.
 
I
All true, but there is a golden recommendation if you plan to get old with your new GPU, if your PSU this is now out of warranty then buy a fresh and keep the old as spare.



Well here is some Greek style teaching , no free fish, but of how to learn to get one by your self.
Corsair CX750 W (the good made version), this deliver 1150Watt before protection activates.
Now calculate the headroom from 750W up to 1150W by you offering to us this value as percentage.

I've hurt two 850w PSU's over the years while folding on old hardware, a Corsair and a Thermaltake. Always because I was pushing for max clocks over extended periods. I have seen over 950w come from an 850, but those 2 850s cannot put out anywhere near their rated wattage anymore. The rails are super bendy, and cannot sustain any kind of oc on that system.
 
Spot on.

Too many hyoerconservatives here for sure..lol.

For theast 2o years I've bought psus where the stress test load is no more than 80% of the psu's limit. Through dozens of builds for myself and clients I never ran these at 50%. So while it is true that they last longer... if you get a quality lsu with a 7-10 year warranty like you should in the first place, you dont need to overspend on additional wattage because of some convoluted idea in people's heads about running at 50% or something.
100%.
 
Igor in Germany his is the only reliable source so far for making electrical measurements over PC hardware.
Yeah right. LOL
Nvidia recommend a 850 watt power supply, do you believe people plucked that figure out their asses?.
Note okidna's screen shot and pay particular attention to the fine print. #2 specifically where it says (my bold underline added),
2 - Requirement is made based on PC configured with an Intel Core i9-10900K processor. A lower power rating may work depending on system configuration.

The point is, no manufacturer (or PSU calculator) wants to recommend an underpowered PSU. So they don't - and rightfully so.

Too many hyoerconservatives here for sure..lol.
I agree. But then I think there are too many of all the extremes. That is, there are some who are convinced bigger is always better so they buy 1200W Titanium when a 600W Gold is more than enough. Then there are some who run the numbers, come up 350W maximum so they insist on getting a 350W (I can only hope at least Bronze) - leaving no room for any upgrades a couple years down the road. Then there are some who, no matter what, say getting a quality 650W is the way to go.

If those were the only 3 options, I supposed I would be in the 650W camp as that typically is safe without going too far overboard. Even with a power hungry system, it is very rare for both the CPU and GPU to max out demands at the same point in time.

But the right way is to really do your homework, research all the individual components (motherboard, RAM, CPU, GPU, fans, drives and everything else that will get power from the PSU), plan ahead for any possible upgrades in a year or two, add a little buffer for aging and perhaps quieter operation, then calculate your needs from there. I used to do that, then added 50 to 100W for good measure and [hopefully] quieter operation (accepting the fact that 50 and 100W are arbitrary).

But now I'm too old and got lazy so I use the Outervision PSU Calculator because it is the most flexible and conservative. Though of course, it too pads the results - just not as much as less flexible and less extensive calculators.
you dont need to overspend on additional wattage because of some convoluted idea in people's heads about running at 50% or something.
I agree again. I never understood that either. I can only assume that 50% figure came from ancient history - long before the 80 PLUS certification program came about, when basic PSUs were the norm and that 50% was where they provided peak efficiency. But even then, I think 70% better represented the typical bell curve peak there. Either way, I agree, doubling is going overboard unless you know for a fact you will be adding a second graphics card and a more powerful CPU next year.
 
Aside from all the points already made it's about the lowest common denominator, and has always been; recommanded PSU wattage for GPU's have always been overestimated. If a card actually pulls 200W it is much safer to recommend 650W becuase some 650W units will be overrated 400W units. Thankfully there are less truly crap PSU's around these days (at least where I live) and the most popular PSU's are Corsairs and Seasonics, and even if the lower end Corsairs are pretty shoddy they are head and shoulders above bargain "GreatUnicornHuntWall 800W €12.99" units, but there are still lots of subpar stuff around.
 
750 should handle it.
 
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