[SOLVED] Possible GPU Bottlenecking problem? GPU-Z showing Idle under load ?

LordMikeus

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Sep 23, 2016
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Hi all!

I've noticed for a while now that despite my GPU hitting 100% usage when doing something intense, say Skyrim VR (modded) and Streaming at the same time, my GPU still shows as Idle inside of GPU-Z. CPU seems to comfortably sit at max like 50% and I've not noticed any noticable problems with temps or power. On my Skyrim example. I hit 99% GPU usage right away, temps are still under 70 and power comsumption (%) in GPU-Z shows as around 65. Wondering if something is stopping the GPU being at it's best performance. It always seems to be idle when gaming despite hitting near 100%. I stream with Nvenc (new) which I believe uses it's own area of the GPU to encode anyway so surprised that it is still so intense. How do I figure out if I need to improve something in my PC or if it's a problem somewhere?

Edit: I do have the system set to prefer Maximum Performance and actuall set Skyrim VR to be Max Performance automatically

My specs are:
B450 Tomahawk Max
Ryzen 5 3600x
32Gb DDR4 G-Skill RAM (2 x 16)
Nvidia GeForce RTX 2080

Any help is appreciated!
 
Solution
I think you're right. I seem to be hitting the cap of my VRAM a fair bit. Notice that even on Warzone. Not sure if I can do anything about that?
Lowering VRAM usage is pretty simple: drop some memory-intensive details such as textures, shadows, reflections, etc. resolution down a notch.

Lutfij

Titan
Moderator
Frequency of the rams used?

Make and model of your PSU and it's age? Make sure you're on the latest BIOS version for your motherboard, then see if you've got updates pending for your OS. Ideally you should be on version 21H1 for Windows 10. Use DDU to uninstall your GPU drivers then manually reinstall said driver in an elevated command, i.e, Right click installer>Run as Administrator.

You stream and game off the same system?
 

LordMikeus

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Sep 23, 2016
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Frequency of the rams used?

Make and model of your PSU and it's age? Make sure you're on the latest BIOS version for your motherboard, then see if you've got updates pending for your OS. Ideally you should be on version 21H1 for Windows 10. Use DDU to uninstall your GPU drivers then manually reinstall said driver in an elevated command, i.e, Right click installer>Run as Administrator.

You stream and game off the same system?

G.SKILL 32GB DDR4 Ripjaws V for Intel. I have them running at 3200 tho as 3600 BSOD's me. Fairly certain my PSU is an Aerocool 80 PLUS 600W PSU. I do think it's been a few months since I did BIOS, was using a tool for it I now can't find or remember. I'll manually do that before I update windows. I haven't moved up to 21h1 yet but I can do that. Not used DDU, seems complicated from a quick glance but I'll do that too after updating Windows to 21H1. Is using GeForce Experience as Admin fine for updating the drivers?

I do stream and game from the same system, have done so for a lot of this year so far.

Edit: Found the tool. I normally use Live Update 6 for updating my Bios I believe and whatever else it tells me to do that seems important. Is that fine?
Had a look at DDU, seems chill. I'll update windows now before I do DDU and BIOS with Live Update and GeForce Experience if they're fine to use
 
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Hi all!

I've noticed for a while now that despite my GPU hitting 100% usage when doing something intense, say Skyrim VR (modded) and Streaming at the same time, my GPU still shows as Idle inside of GPU-Z. CPU seems to comfortably sit at max like 50% and I've not noticed any noticable problems with temps or power. On my Skyrim example. I hit 99% GPU usage right away, temps are still under 70 and power comsumption (%) in GPU-Z shows as around 65. Wondering if something is stopping the GPU being at it's best performance. It always seems to be idle when gaming despite hitting near 100%. I stream with Nvenc (new) which I believe uses it's own area of the GPU to encode anyway so surprised that it is still so intense. How do I figure out if I need to improve something in my PC or if it's a problem somewhere?

Edit: I do have the system set to prefer Maximum Performance and actuall set Skyrim VR to be Max Performance automatically

My specs are:
B450 Tomahawk Max
Ryzen 5 3600x
32Gb DDR4 G-Skill RAM (2 x 16)
Nvidia GeForce RTX 2080

Any help is appreciated!
how can gpu be idle if its hitting 100% usage?
high gpu usage while not hitting power limit doesnt mean gpu is idle, it just means gpu board power design was overdesigned...so you can overclock your GPU tu push its performance beyond its normal limits
 

LordMikeus

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Sep 23, 2016
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how can gpu be idle if its hitting 100% usage?
high gpu usage while not hitting power limit doesnt mean gpu is idle, it just means gpu board power design was overdesigned...so you can overclock your GPU tu push its performance beyond its normal limits

Hi, sorry, this was based on GPU-Z showing Perf-Cap reason as Idle, that is my bad for not specifying. It shows this despite Task Manager showing 99% and GPU-Z shjowing the same (GPU Load inside of GPU-Z). I was under the impressions this implies a problem? I'm unsure how to overclock my GPU but if that is the solution and my 2080 is just at it's limits from what I'm doing, I can take a look at that. I did believe it shouldn't be hitting 99% though, I thought a 2080 would handle what I'm doing pretty well. Even if I stream using x264 as the encoder, my GPU hits 99% while streaming Skyrim VR.
 
Hi, sorry, this was based on GPU-Z showing Perf-Cap reason as Idle, that is my bad for not specifying. It shows this despite Task Manager showing 99% and GPU-Z shjowing the same (GPU Load inside of GPU-Z). I was under the impressions this implies a problem? I'm unsure how to overclock my GPU but if that is the solution and my 2080 is just at it's limits from what I'm doing, I can take a look at that. I did believe it shouldn't be hitting 99% though, I thought a 2080 would handle what I'm doing pretty well. Even if I stream using x264 as the encoder, my GPU hits 99% while streaming Skyrim VR.
if perf cap reason is idle..hmm ye theres a problem
can u run nvidia-smi -q command in windows\system32 location command and post result on pastebin ,then post link
 
Hi, sorry, this was based on GPU-Z showing Perf-Cap reason as Idle, that is my bad for not specifying. It shows this despite Task Manager showing 99% and GPU-Z shjowing the same (GPU Load inside of GPU-Z). I was under the impressions this implies a problem? I'm unsure how to overclock my GPU but if that is the solution and my 2080 is just at it's limits from what I'm doing, I can take a look at that. I did believe it shouldn't be hitting 99% though, I thought a 2080 would handle what I'm doing pretty well. Even if I stream using x264 as the encoder, my GPU hits 99% while streaming Skyrim VR.
Any sort of % Utilization statistic is just how often did the thing in question spent not idling.

The PerfCap reason does not imply there's a problem. It simply means why the GPU isn't boosting further, and it's likely that "Utilization" is a default answer because the other reasons aren't being met. In my case, since I detuned my GPU a little bit, I'm always hitting the "Util" perfcap reason because none of the other conditions are met:
  • I'm not hitting Power because I'm always under the TBP of the board
  • I'm not hitting Thermal because the board is never overheating
  • I'm not hitting Vrel or Vop because I set a voltage cap of 0.95V
So what else does the GPU have to report?
 
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Any sort of % Utilization statistic is just how often did the thing in question spent not idling.

The PerfCap reason does not imply there's a problem. It simply means why the GPU isn't boosting further, and it's likely that "Utilization" is a default answer because the other reasons aren't being met. In my case, since I detuned my GPU a little bit, I'm always hitting the "Util" perfcap reason because none of the other conditions are met:
  • I'm not hitting Power because I'm always under the TBP of the board
  • I'm not hitting Thermal because the board is never overheating
  • I'm not hitting Vrel or Vop because I set a voltage cap of 0.95V
So what else does the GPU have to report?
well than pcb is overengineered...never had GPU which would run below PCB potential
mine current 1070ti had to be moded to get more power to it and im still hitting power limit (at 2240MHz)
 

LordMikeus

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Sep 23, 2016
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Sorry, convo got a bit more advanced than I'm knowledgable on overnight! :D

From what you said @hotaru.hino , it still sounds like you're hitting a maximum utilization perfcap, so the limits of your GPU are being hit? Does GPU-Z then show reason as Util as you're at the cards maximum ability? Mine never changes from Idle so I feel if I reach 99% usage and performance tanks, then I should see reason change to Util too if I've hit the GPU limit? I may have misunderstood what you mean as I know you said the perfcap doesn't imply a problem, but reading the rest it still sounds like I should seeing a reason other than Idle?

Still a bit advanced for me as not sure on what you mean by overengineered @kerberos_20 but sounds like even on an older card you hit the power limit of the system using your GPU? I do think my PSU is a Bronze older one at this point but I'm unsure how to tell if power is throttling the card unless perfcap tells me.
 
Sorry, convo got a bit more advanced than I'm knowledgable on overnight! :D

From what you said @hotaru.hino , it still sounds like you're hitting a maximum utilization perfcap, so the limits of your GPU are being hit? Does GPU-Z then show reason as Util as you're at the cards maximum ability? Mine never changes from Idle so I feel if I reach 99% usage and performance tanks, then I should see reason change to Util too if I've hit the GPU limit? I may have misunderstood what you mean as I know you said the perfcap doesn't imply a problem, but reading the rest it still sounds like I should seeing a reason other than Idle?

Still a bit advanced for me as not sure on what you mean by overengineered @kerberos_20 but sounds like even on an older card you hit the power limit of the system using your GPU? I do think my PSU is a Bronze older one at this point but I'm unsure how to tell if power is throttling the card unless perfcap tells me.
mine isnt throttling...it runs stable clock...higher clock would need more voltage and additional power board...but i doubt its needed :p
 
well than pcb is overengineered...never had GPU which would run below PCB potential
mine current 1070ti had to be moded to get more power to it and im still hitting power limit (at 2240MHz)
It's not over engineered. I have mine running with an undervolt for efficiency. If I let it run on its default profile, it'll most likely hit Vrel or Power.

And I get barely anything more out of it anyway, so that's why I don't let it run on its default profile.

From what you said @hotaru.hino , it still sounds like you're hitting a maximum utilization perfcap, so the limits of your GPU are being hit? Does GPU-Z then show reason as Util as you're at the cards maximum ability? Mine never changes from Idle so I feel if I reach 99% usage and performance tanks, then I should see reason change to Util too if I've hit the GPU limit? I may have misunderstood what you mean as I know you said the perfcap doesn't imply a problem, but reading the rest it still sounds like I should seeing a reason other than Idle?
Here's an example of why seeing "Idle" or "Utilization" isn't a necessarily a problem.

EDIT: I'm going to show some benchmark scores, ignore the score, I'm not trying to aim for getting a high score and this is purely to demonstrate something. So while, spoiler alert, the scores are lower than the average, this is necessarily not a problem. And I've gotten this hardware to push well past the average.

This is a 3D Mark Time Spy run with my video card, a 2070 Super, running on its default profile:
sJ1ZHMH.png


Here it is with my tuned profile, which is basically VF curve tweak that looks like this:
5388jHl.png


And here's what I'm getting on 3D Mark Time Spy with this profile
mwDpE1x.png


If you look at the GPU-z plots, I'm basically getting the same results at first glance. However, the PerfCap reason in the tuned profile is "Idle" the entire time, whereas using the default profile had hit the power limit. So arguably the card is still pushing to most of it's potential. But back to the point of why I'm saying ignore PerfCap reason for the most part is my card is physically not hitting any of the other conditions and the thing must report something, so it defaults to "Idle"

So basically this is the reason why I 1. tune my video card and 2. am showing that PerfCap reason doesn't necessarily imply there's a problem. It's only really a concern if you're trying to eke out every last megahertz on your card and in my card's case, I'm only able to get a +70MHz to my boost. Which in the grand scheme of things is like maybe 3-4%.
 
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LordMikeus

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That makes sense I think. I understand that you have a defualt profile and a tweaked one. Default hits power limit and for the tweaked profile it hits no limit but I assume usage is still at 99-100% when running that benchmark? My problem was that hitting 99% completley lagged out my game, making it unplayable, all while still showing idle. That made me believe that there was a problem as I didn't think my 2080 would be at it's limit from what I was doing, but perhaps I'm wrong? I thought something must be bottlenecking it but GPU-Z wasn't telling me what.
Maybe confusing myself a bit here :tearsofjoy: I thought perfCap would tell me what was freaking out the GPU. So if it's Idle despite freaking out, it just means the GPU isn't strong enough for everything I'm doing on it? It's nothing else limiting it?
 
That makes sense I think. I understand that you have a defualt profile and a tweaked one. Default hits power limit and for the tweaked profile it hits no limit but I assume usage is still at 99-100% when running that benchmark? My problem was that hitting 99% completley lagged out my game, making it unplayable, all while still showing idle. That made me believe that there was a problem as I didn't think my 2080 would be at it's limit from what I was doing, but perhaps I'm wrong? I thought something must be bottlenecking it but GPU-Z wasn't telling me what.
Maybe confusing myself a bit here :tearsofjoy: I thought perfCap would tell me what was freaking out the GPU. So if it's Idle despite freaking out, it just means the GPU isn't strong enough for everything I'm doing on it? It's nothing else limiting it?
It's unlikely it's the GPU's fault if 99.9% of the time the GPU is fine running the game and all of a sudden there's a hiccup. It's more likely that the CPU being overly taxed, something in the application, or something else like a driver hiccup or whatnot caused a hitch.
 

LordMikeus

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It's unlikely it's the GPU's fault if 99.9% of the time the GPU is fine running the game and all of a sudden there's a hiccup. It's more likely that the CPU being overly taxed, something in the application, or something else like a driver hiccup or whatnot caused a hitch.
It doesn't run fine at all for Skyrim VR while streaming it. Obviously that's a pretty taxing combo but I thought Nvidia Nvenc new ran on it's own thing anyway and wouldn't tax the GPU so much that the game is unplayable. GPU usage hit's 100% in Task Manager, GPU-Z shows idle and the game is unplayable and laggy. So if it's not being bottlenecked by something else, it sounds like the GPU just can't handle the combo to me, which is suprising. Even if I stream on x264 encoder which uses CPU I thought, GPU still hits 99% and game becomes unplayable.
 
It doesn't run fine at all for Skyrim VR while streaming it. Obviously that's a pretty taxing combo but I thought Nvidia Nvenc new ran on it's own thing anyway and wouldn't tax the GPU so much that the game is unplayable. GPU usage hit's 100% in Task Manager, GPU-Z shows idle and the game is unplayable and laggy. So if it's not being bottlenecked by something else, it sounds like the GPU just can't handle the combo to me, which is suprising. Even if I stream on x264 encoder which uses CPU I thought, GPU still hits 99% and game becomes unplayable.
when you not streaming/recording, everything is fine?
 

InvalidError

Titan
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It doesn't run fine at all for Skyrim VR while streaming it. Obviously that's a pretty taxing combo but I thought Nvidia Nvenc new ran on it's own thing anyway and wouldn't tax the GPU so much that the game is unplayable.
NVEnc does run on dedicated hardware and should have negligible to no impact on overall GPU performance. If "streaming using NVEnc" destroys performance, something either isn't configured correctly or not working as expected.

If Skyrim VR generates a 3rd view for streaming instead of reusing the left or right eye view, that would also increase rendering workload by 50%.
 

LordMikeus

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NVEnc does run on dedicated hardware and should have negligible to no impact on overall GPU performance. If "streaming using NVEnc" destroys performance, something either isn't configured correctly or not working as expected.

If Skyrim VR generates a 3rd view for streaming instead of reusing the left or right eye view, that would also increase rendering workload by 50%.
I currently stream using the VR Capture method. I get the same result for both SLOBS and OBS Studio, both of which capture the right eye. The game is technically displayed on my desktop but it's not what I capture I believe. Perhaps I should try capturing what is displayed there instead? I do think this has been a problem on a lot of games though. I thought getting some serious impact from streaming on NVenc new was normal. How would I figure out if it's working correctly or where my problem may be?
The game does run fine not streaming, but the second the stream is up either on x264 or NVence new, my GPU goes apeshit and game becomes unplayable it seems.

On a side note, I run Cyberpunk 2077 on RayTracing Ultra settings while having chrome up and watch a friend stream through Discord on another monitor. Albeit, that seems far more CPU based than GPU but even then, runs fine. Could things like running SKyrim VR as Admin or anything be affecting stuff? Really baffled.
 
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InvalidError

Titan
Moderator
I was going to say "maybe OBS is getting the NVEnc stream from the GPU and then decoding it on the CPU to add stream overlays before re-encoding the whole thing" but if you only see 50% CPU usage, that probably isn't the case.

If OBS does stream overlay processing on the GPU before encoding, then it needs to allocate a bunch of buffers on the GPU to process the layers on. You should take a look at VRAM utilization, 8GB might be too tight.
 

LordMikeus

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I was going to say "maybe OBS is getting the NVEnc stream from the GPU and then decoding it on the CPU to add stream overlays before re-encoding the whole thing" but if you only see 50% CPU usage, that probably isn't the case.

If OBS does stream overlay processing on the GPU before encoding, then it needs to allocate a bunch of buffers on the GPU to process the layers on. You should take a look at VRAM utilization, 8GB might be too tight.
I think you're right. I seem to be hitting the cap of my VRAM a fair bit. Notice that even on Warzone. Not sure if I can do anything about that?
 

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