Why do I get poor frame rates when my GPU isn't working hard? (VR)

[dan0812]

Quite new to [modern] gaming PCs. I have an i7-9700f, 16GB RAM and an RTX 2060 6GB. Using a Quest 2 at 72Hz.

This relates solely to driving games with just me on the track. Other VR ganes run fine. My CPU doesn't seem to go much over 70% when playing any of these.

Dirt Rally - GPU is <70% use and frame rate was very choppy using recommended settings (or even slightly below them). Only when I dropped all settings to the minimum and GPU was <50% did I get steady frame rate,

AMS2 and PCars2- GPU is <80% but, depending on the track, I get bad stutter when slowing and accelerating for corers which creates a warping effect.

AC - just works!

I'm trying to understand why this happens. My CPU definitely isn't a weak point so is it unoptimised games or lack of GPU power despite it seemingly not being pushed to its limits?

 

[mooneyman]

I use flight sims more than driving ones (still like AC though!) and have a fairly decent PC.
I find in a sim such as Rise of Flight (a WW1 flight sim) which has been out a fair while, I cant crank the eye candy up to full without serious stutter occuring.
Whereas newer games can have all the bells and whistles with smooth gameplay.
This is down to bad game engine optimisation and cant really be overcome,I suspect that is the case with you.
PS - This is not saying newer games always run better....you can still get a modern game that fails to get the full potential out of itself,by poor coding.

 

[Terry Rock]

Quite new to [modern] gaming PCs. I have an i7-9700f, 16GB RAM and an RTX 2060 6GB. Using a Quest 2 at 72Hz.

This relates solely to driving games with just me on the track. Other VR ganes run fine. My CPU doesn't seem to go much over 70% when playing any of these.

Dirt Rally - GPU is <70% use and frame rate was very choppy using recommended settings (or even slightly below them). Only when I dropped all settings to the minimum and GPU was <50% did I get steady frame rate,

AMS2 and PCars2- GPU is <80% but, depending on the track, I get bad stutter when slowing and accelerating for corers which creates a warping effect.

AC - just works!

I'm trying to understand why this happens. My CPU definitely isn't a weak point so is it unoptimised games or lack of GPU power despite it seemingly not being pushed to its limits?

What motherboard and power supply are you using?
If you don't have enough amperage on the rails, things will become marginal at peak power usage.
Can you supply a list of programs running on your PC?
If programs are starting during gameplay, that can tap into resources and cause stuttering.
How are the hard drives configured in terms of their connections to the board?
If they're not on optimal controllers, you could be giving up performance right from the start.
All of these things make a massive difference to how games run.
I'm not saying it is your issue necessarily but I do see folks suffering from these issues all the time without having a look at configuration.

 

[dan0812]

What motherboard and power supply are you using.....

It's an off the shelf HP with a proprietary motherboard and 500w PSU. I know....but the retailer accidentally double discounted it so it was a bargain.

Came with a small NVME and an HD - only change I made was to add an SSD for games on the free SATA port (there was only one).

I have disabled everything I don't need. All that opens with windows is:

steam client
nvidia stuff
steel steries mouse software
surfshark vpn
clcleaner
superantispyware
virtual desktop streamer
some HP crap I've only just seen was showing in Ccleaner despite disabling everything in windows startup.

I've trimmed that down and taken off the last four from startup and will see if it makes any difference. Oh, and simhub and Oculus which I need.

Edit - no difference.

 

[Killg0reNL]

Give fpsVR a try, it might help you with with finding the bottleneck. And perhaps memory bandwidth is poor? So all the stuttering comes from there? I am also rather new to VR so can't give you exact help.

On ACC the faster the memory, the better it runs. Might be for other games aswell.

Use cpu-z and gpu-z to figure out how youre hardware is set.

 

[Terry Rock]

It's an off the shelf HP with a proprietary motherboard and 500w PSU. I know....but the retailer accidentally double discounted it so it was a bargain.

Came with a small NVME and an HD - only change I made was to add an SSD for games on the free SATA port (there was only one).

I have disabled everything I don't need. All that opens with windows is:

steam client
nvidia stuff
steel steries mouse software
surfshark vpn
clcleaner
superantispyware
virtual desktop streamer
some HP crap I've only just seen was showing in Ccleaner despite disabling everything in windows startup.

I've trimmed that down and taken off the last four from startup and will see if it makes any difference. Oh, and simhub and Oculus which I need.

Edit - no difference.

What does CPU usage show if you run a CPU-heavy stress test like Prime95?
Define "opens with Windows"....are we talking about the program auto-loading into memory on Windows startup and staying minimized on the taskbar?
If so, go into startup programs and stop that from happening.
It is very easy to launch anything you need in this day of super-fast SSD drives.
As to antivirus stuff... I assume you are running some variant of Windows10.
Get rid of that additional 'superantispyware'.
HP computers generally come with all kinds of bloatware.
Make a backup of any software you think you'll use in the future, then try to remove the components you don't currently use.
500 watts may be on the paltry side depending on what components are in the system.
It doesn't sound like you have too many USB things running but a good powered hub might help a bit.
Try these things to see if it helps.

 

[dan0812]

..... HP computers generally come with all kinds of bloatware ...

I think you're onto something!

I discovered a lot of HP junk lurking some of which could only be stopped by disabling it in the registry.

Just gave AMS2 a try and, apart from a couple of minor sound stutters, it worked! I didn't get any noticeable frame drops on the problem tracks.

I thought I had a pretty lean windows installation but I guess not. Hopefully this sorts it for good.Thanks!

 

[Case_]

If your GPU usage is below 95-ish percent and you get framerate drops, it means you're CPU limited in some way. CPU utilization (overall or per core) won't tell you much on modern CPUs. With your CPU, you can be completely CPU limited with as little as 12-13% CPU utilization and with no individual core visibly utilized fully if the game you're running can only utilize a single thread, and with pretty much any CPU utilization above that if it uses more than one thread.

 

[dan0812]

If your GPU usage is below 95-ish percent and you get framerate drops, it means you're CPU limited in some way. CPU utilization (overall or per core) won't tell you much on modern CPUs. With your CPU, you can be completely CPU limited with as little as 12-13% CPU utilization and with no individual core visibly utilized fully if the game you're running can only utilize a single thread, and with pretty much any CPU utilization above that if it uses more than one thread.

OK but how do I know that's the case and what an I do about it? It's a pretty decent CPU I think, above the recommended and I'm running the game on minimum specs.

Unfortunately AMS2 despite my optimism was running like crap today with a warp effect on every corner - on pretty much the barest, shortest track.

 

[kevin ohara]

Are you connecting the Quest 2 via cable or using wireless and Virtual Desktop? I found using my cable connection either to my RTX2080 c port or a USB 3 port that I get poor performance in driving games. I ended up using wireless with Virtual Desktop and got better performance. Using a cable I get graphic artefacts which I do not get on wireless. You'd expect to get the opposite as using wireless would expect it to perform worse than on direct cable. I don't have the official cable but cable I have tests fine with over 1.7gbs speed.

 

[dan0812]

Are you connecting the Quest 2 via cable or using wireless and Virtual Desktop?

It seems better through VD but there is a noticeable drop in quality -the image looks a bit softer.

This made me wonder if there's any benefit to launching it via Steam VR vs. Oculus as I normally do. It seemed better via Steam VR but I would have to test for a lot longer (I'm bored of testing now).

There does seem to be an issue with madness engine due to all the similar comments I found about PCars 2 not all of which mentioned VR. The frame skips happen even at 180FPS in 1080p - only capping well below that ensures it runs smoothly. For VR I had to cap it at 30FPS.

At least with Dirt Rally the choppyness was consistent and I could just drop settings to sort it out AMS2 manages to run great for a bit then is all over the place even if I run it so it looks like a PS1 game.

 

[RasmusP]

OK but how do I know that's the case and what an I do about it? It's a pretty decent CPU I think, above the recommended and I'm running the game on minimum specs.

Unfortunately AMS2 despite my optimism was running like crap today with a warp effect on every corner - on pretty much the barest, shortest track.

A few things about CPU:
As Martin said earlier, you can't see the CPU limit apart from when the overall load is 99%.
The issue is that you can't see if one core is maxed out.
Task Manager and other tools show CPU loads with an interval of mostly 1 seconds.
That means EACH of your cores did 4.5 billion cpu cycles (4.5 GHz) and all of them are averaged..

Our simracing games mostly only use 2-4 cores so you a 10 core CPU won't show any improvement over a 5 core CPU.
All you need are 5 cores and the maximum possible single core performance.

Your 9700f only boosts to 4.5-4.6 GHz as soon as 3 cores are used. The 9700k would easily be overclocked to 5.0 GHz, so you lose a bit of performance there.

Then the non k CPU probably won't come with a Z motherboard, since you can't overclock the f CPU anyway.
This sadly also means that your maximum RAM clock is 2666 MHz.

Our simracing games get a good boost from higher memory clocks.
Here's an overview I did with my 10600k in ACC (other simracing titles might show similar results):

BUT I'm not saying that it is your raw CPU performance. It also might be the CPU becoming too hot and throttling down due to cooling or background stuff running in the background.

At 72 Hz, your 9700f with 2666 ram should be good enough!
Only at 90 Hz like the Oculus Rift it would become problematic.

What you should do:
As mentioned earlier use fpsVR and check the frametimes.
It should show how much ms it took the CPU to render the frame and how long it took the GPU to render the frames.
One of them will show below 72 fps (= 13.89ms frame to frame).

At least with Dirt Rally the choppyness was consistent and I could just drop settings to sort it

Dirt Rally showed really weird behaviour for me!
I only had the Oculus Rift for 3 months so I am no great help for VR stuff.

However the oculus tray tool (some analysis and tweaking program for Oculus headsets) showed that my CPU had enough headroom to maintain 90 fps and my GPU (GTX1070 back then) also had enough headroom.
But as soon as my GPU load got above 50%, the fps dropped.

It didn't make sense, it still doesn't make sense.. In the end I set the Oculus to force ASW (45 Hz with interpolated frames) and used high settings.
To maintain 90 fps, the game had to look super ugly, not worth it...


I hope that was some useful information for you.

What you should do:
- fpsVR will show you what's the issue, CPU or GPU
- download CPU-Z and tell use your ram speed (it will show half of the true value, don't wonder) and also tell us your motherboard!

- If you wanna check if your CPU is performing like it should: download Cinebench R15 and do a few "multi" runs in a row. Check if your score is going down (cooling not good enough).
And also tell us your score so we can check if it makes sense or there's a problem.

 

[dan0812]

A few things about CPU...

Thanks for the post.

CPUZ-z said 1333 as I expected it to.

This is the motherboard:

HP Desktop PCs - motherboard specifications, Edoras | HP® Customer Support

Specifications for the Edoras motherboard

support.hp.com

Ran Cinebench repeatedly - CPU always went straight to 100%:

1187
1116
1042
1119
1084
1130
1079
1086
1092
1097
1048
1062
1141
1103
1059
1072
1073
1135
1091

I will have a look at FPSVR when I get the chance.

 

[dan0812]

FPSVR was a waste of time - doesn't work with AMS2 or PC2.

 

[Turk]

OK but how do I know that's the case and what an I do about it? It's a pretty decent CPU I think, above the recommended and I'm running the game on minimum specs.

Minimum specs are a bit of a shot in the dark when it comes to VR. The bottom line is when it comes to sim racing in VR, the top of the range systems are still struggling, VR is about the most demanding thing you can ask of your PC. I turn off everything that cane be turned off. I even found my monitor software was interfering with VR because it picked up the headset as a display and wanted to control it.
I turn off all backup, monitor software, VPNs, super anti spyware, TeamViewer.

But over all sacrifices have to be made with graphics. In ACC I'm currently running everything on medium to low and 60% resolution on a HP G2, CPU is a 8086K @ 5ghz and a 2070 super. I just had to keep dropping settings until I got a stable 90fps.

Are you getting stutters no matter how low you set the graphics?

 

[dan0812]

Are you getting stutters no matter how low you set the graphics?

Yes and the issue isn't exclusive to VR. I ran the game (AMS2) at over 200FPS in 1080p and it still stuttered. The only way to fix it was to v-sync it at 60FPS. Similarly, I can cap the frames in VR at something like 40 and it will run OK.

I've seen comments from people with very high spec PCs saying performance in AMS2 is poor and others with much lesser systems saying they get good results.

 

[Turk]

Yes and the issue isn't exclusive to VR. I ran the game (AMS2) at over 200FPS in 1080p and it still stuttered.

That does sound like there's something wrong so. Is it happening in other titles outside of sim racing like other games? Or randomly while using windows?

 

[pattikins]

FPSVR was a waste of time - doesn't work with AMS2 or PC2.

FPSVR works fine in PC2 & AMS2.

Maybe you should think about reinstalling AMS2 - I didn't encounter any problems with the game and it ran without issue (90fps Odyssey+) in VR.

Which version of Cinebench did you use?

Whilst in VR try running MSI afterburner in the background to log your cpu threads - if one or more of your threads are getting saturated then it's a matter of identifying the cause, i.e., it could be Chrome apps running in the background (irrespective if Chrome is open)...

 

[dan0812]

That does sound like there's something wrong so. Is it happening in other titles outside of sim racing like other games? Or randomly while using windows?

Just AMS2 and PCars 2 suffer from the stuttering, Dirt Rally and AC run smooth at appropriate settings.

FPSVR works fine in PC2 & AMS2.

Not for Oculus unfortunately - something to with some games connecting direct to Oculus software rather than Steam VR and it can't get the data it needs.

I used Cinebench R15 as suggested.

I did do a fresh install of AMS2 and it seemed to run slow (without stutter) - not sure why. The constant stop, start and testing feels like a bit of a chore at this point and I've left it a few days but will try it again later.

 

[pattikins]

Just AMS2 and PCars 2 suffer from the stuttering, Dirt Rally and AC run smooth at appropriate settings.



Not for Oculus unfortunately - something to with some games connecting direct to Oculus software rather than Steam VR and it can't get the data it needs.

I used Cinebench R15 as suggested.

I did do a fresh install of AMS2 and it seemed to run slow (without stutter) - not sure why. The constant stop, start and testing feels like a bit of a chore at this point and I've left it a few days but will try it again later.

I hope it's not to late for you to get your money back for fpsVR.

I was expecting to see three digit results for your Cinebench tests, running 3 or 4 threads. If the results are for all 8 threads, then I'm guessing it should be around the 1500 mark. Have you done a 6 thread test?

Have you recently updated your graphics or Oculus drivers?