Power supply check

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1

This is my current spec:
2x E5-2660v3
4x16GB DDR4 2100 (1.2v)
1 x 512GB 970 EVO
4 x 250GB 970 EVO via Asus Hyper m.2 X16 Card
1 Asus Xonar Essence STX
2 x EVGA GTX 1080ti FTW3 SLI

What do you guys recommend as the power supply requirement? 1000 watt? I am currently using an 850 watt power supply but @ 4k ultra settings (at least Battlefield 1) and i’m getting like 80 fps which dips to 70fps. GPU utilization is at 70% on both cards and CPU is not hitting 100% utilization at all.

I am thinking that the cards are not drawing enough power? I’m also trying to figure out how to check if power is an issue when monitoring these cards, what do you guys recommend to use? HWInfo? Afterburner?

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Not a power issue at all. Check CPU utilization.

NVM missed the part where you are at 4k.

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(TAA turned on)

Screenshot example of utilization. It’s quite odd. It doesn’t seem like CPU is bottle necking. Unless I am reading this wrong.

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Well it’s clear it’s not really threading properly but no, that’s not the problem.

What happens if you drop SLI and run on a single card?

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I get about 70fps. which is slightly lower. The weird thing is that I have seen people get above 100fps in this game with 1080ti sli with the same settings. https://www.youtube.com/watch?v=m7pEZyBtQls

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Really don’t think this is a psu problem.

Too many possible bottlenecks:

  • SLI efficiency
  • VRAM bottlenecking with the high resolution
  • System RAM not keeping CPU fed can cause drop in framerates

#edit: Overclocked 1080ti’s can draw about 300-330w and the CPU has a TDP of 105w so even though I don’t think the performance is related to power you are currently close to the max of your PSU

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You probably have, and then an update comes along or something a breaks SLI for no good reason or something dumb like that.

SLI was the tech we wanted but never really got.

As far as your setup goes 850 is plenty. I dont see any issue with the parts other than the dual xeons are not suited to “macksimum gaymen performince” but theres no reason you shouldnt hit 100% GPU @4k because you become limited by any GPU at that res.

I have no experience with current SLI though (last time I did it I was using 2x 9800gtx+) so maybe @KuramaKitsune can offer some insight here? I think hes got an SLI setup (man I would look like an asshole if he doesnt).

Yeah, I would think if hes hitting a PSU wall the thing would go into protect and just shut off. I suppose we could test this by dropping power target in whatever OC utility he prefers.

8

Hmm this is really strange. I closed the game and relaunched. I’m actually getting close or not the same FPS ±10 but mostly above 100fps even in high action areas. I also noticed that the GPU now is utilizing 80% instead of 60 before. I did look at HWInfo throughout the test run and notice that it did not report Power Limit. I will do more testing later today. It is slight weird that it performs in one extreme and then another with just a game restart.

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I am definitely rethinking SLI. I picked up the card from my friend cause he’s getting rid of it for the 2080ti. I might just return it if there’s too much performance fluctuation.

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One interesting I noticed now is that while the FPS are close to what other people are showing, I am seeing less sudden drastic FPS drop. But overall it’s about a 30% increase in performance.

Thank you guys for replying so quickly and help me understand that it’s not a PSU problem.


(TAA Turned off, 65% both gpu usage if TAA is on)

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12

cpu bottleneck, well yeah Xeon E5’s dont clock that high.
But 70% utilization on both cards is pretty good on that cpu.

Nothing to do with power problems.

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How can you tell it’s CPU bottleneck besides the clock speed?

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Well games generally benefit more from higher core clock speeds, rahther then more cores.
Normally on 4K with a single 1080Ti, it would be fine though, because then you will be more gpu bound.
But since you run two 1080Ti’s in sli, and cpu core clocks on that particular E5 is kinda low…
Im exally still suprised that your scaling is that great as it is.
Games basically dont really benefit much from having more then 6 cores nowdays.
But 4K ultra gaming is pretty demending on gpu power, but two GTX1080Ti’s,
should kinda crunch it regardless.

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my 1080s do about 200 watts each ish i wanna say ?

ive got a platinum rated psu the better eff the less heat and waste from the psu
an evga supernova 1000w platnum P2

driving 2 1080s and a 6800k

@Adubs

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I think its that game in particular that scales so well.

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Yeah well most games dont really benefit much from having more then 6 cores really,
unless you do live streaming.
But other then that, it makes more sense to get an i7 / i9 cpu with higher core clocks,
in this particular situation.
Threadripper also sucks in gaming so yeah.

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No I meant SLI scaling. but yeah even with 2 1080tis hes still GPU bound in 4k so the xeons are fine too.

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Yeah well depending on the said game.
In some games he will indeed still be gpu bound,
and in those games he would indeed see a better scaling.
Still 70% isnt that bad for that Xeon E5 though.

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Interesting points guys. I will take some time to digest this.

Also the reason why the scaling might be good on these CPUs are because they’re hacked to have all cores run at Max turbo. Normally the 2660v3 can only hit 2.6ghz on 10 cores turbo. The video of the 1080ti sli I posted earlier on is on threadripper at 3.7ghz and much higher ram speed.

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