Rift-S + 3070 low performance but low charge on CPU and GPU?

[javiersm100]

Hi guys!

Im struggling to get 80fps on my Rift-S when there is more than 10 IA and I don´t undertand why.

I am on:
Ryzen 5 3600
RTX 3070
RAM Vengeance 32 16Gb @ 3200Mhz
Nox Urano 750W
Gigabyte B550M DS3H

Running windows 10 pro, fresh new install without any other software but assetto corsa, oculus soft, oculus tray tool, MSI Afterburner and Chrome. No office, no antivirus, no trash...
Drivers updated to latest versión for GPU and motherboard.

I´ve been doing some test with odd results for me.

Asseto Corsa + Content Manager + CSP 1.74 + Sol 2.0.2 quality settings quite high.
I use Afterburner to monitor CPU and GPU usage and temps. And Oculus Tray Tool to see performance headroom in VR.

On sigle screen at 1080P I get this:

1 car on track with ppfilter sol_extra
250fps to 350 fps
GPU 97% (locking to 60fps GPU goes down to 30%)
CPU 18%


1 car on track no postprocesing
280 fps to 450 fps
GPU 80% to 95%
CPU 15% to 40%

So it looks my PC it´s performing fine, from my point of view.

But when I go VR and put some cars I get this:

1 car on track with ppfilter sol_extra
80 fps
GPU 50%
CPU 10%
headroom performance 25-30%

11 cars on track with ppfilter sol_extra
80fps
GPU 65%
CPU 20%
headroom performance -3% to -20% (still 80fps but with some drops)

Without postprocesing the values are better, not much, but better. About -5 to +17% of headroom performance and GPU 40% and CPU 17% usage.

The odd thing for me is, how can a get so low headroom performance when I put some IA cars but according to afterburer GPU and CPU usage are low?

Temperatures are ok 65 to 72ºC for CPU and 60-65ºC for GPU.

If I raise the amount of cars to 13 or 15 I didnt get 80fps, the ASW kicks in and headroom performance goes -30%.
And GPU during ASW goes to 30-40%, I supose this is normal because there is only 45 frames rendering.
But the hole thing is driving me crazy, how can I get so low performance headroom with such a low charge on GPU and CPU? Where is the problem?

Thank you so much!

 

[GaryGavlaar]

@RasmusP Clocks are showing 4150mhz when cinebench is running....

Here is the screen shots that show what i meant in the last post....

3 cores (look at the utilisation)

And here's where you use all cores (12) (Can also see clock speed in this one)

 

[RasmusP]

I will give this a go cheers.

A little something ive just noticed.... If I run cinebench on 3 cores it doesn't seem to hit 100% utilisation on any of the cores, where as if I run it on all 12, all 12 cores hit 100% utilisation for the whole duration of the test. This doesn't seem right, should I not see 3 at 100%?

That's completely normal!
It's more efficient to put the same rendering thread to the next core after doing one "chunk" of the workload.
I don't know why, but apparently the next core can prepare to read from the cache or something like that.

If you would see 3 cores at 100%, your maximum overall cpu load would be:
12 cpu threads (6c + 6 virtual cores) = 100%
100% / 12 = 8.33% per cpu thread.

3 threads rendering = 3x 8.33% = 24.99% overall cpu load.

But due to windows throwing the rendering thread around on all cpu threads, you end up with a higher overall load!

This is the same reason you can not see a cpu limit in games directly.
You simply can't see if the single thread limit is reached.
In assetto corsa (and with the oculus tray tool and with other VR analysis tools) you can see the frame time for cpu and gpu separately though.
For example you want 100 fps, which means frametime = 10 ms.
And the cpu frametime is 12 ms, the gpu frametime is 8 ms.
Then you know you are cpu limited.
12 ms = 83.33 fps.
8 ms = 125 fps

Hope that makes it a bit clearer?
4100 mhz do look okay for a ryzen 3600x.

Did you check via Taskmanager if something is running in the background?

 

[GaryGavlaar]

That's completely normal!
It's more efficient to put the same rendering thread to the next core after doing one "chunk" of the workload.
I don't know why, but apparently the next core can prepare to read from the cache or something like that.

If you would see 3 cores at 100%, your maximum overall cpu load would be:
12 cpu threads (6c + 6 virtual cores) = 100%
100% / 12 = 8.33% per cpu thread.

3 threads rendering = 3x 8.33% = 24.99% overall cpu load.

But due to windows throwing the rendering thread around on all cpu threads, you end up with a higher overall load!

This is the same reason you can not see a cpu limit in games directly.
You simply can't see if the single thread limit is reached.
In assetto corsa (and with the oculus tray tool and with other VR analysis tools) you can see the frame time for cpu and gpu separately though.
For example you want 100 fps, which means frametime = 10 ms.
And the cpu frametime is 12 ms, the gpu frametime is 8 ms.
Then you know you are cpu limited.
12 ms = 83.33 fps.
8 ms = 125 fps

Hope that makes it a bit clearer?
4100 mhz do look okay for a ryzen 3600x.

Did you check via Taskmanager if something is running in the background?

Ahh ok that's reassuring then.

With regards to tasks running, here is a screenshot of my task manager sorted by CPU. There are things but nothing that's massively taxing from what i can see.....

 

[TylerPL666]

I remember similar problem in other VR Sim - DCS - before I started racing I was spending days digging in EagleDynamics forum, and rememberd well that "MSI" (Dragon Center) and "VR sttutering" were combined toghether. Afterall if MSI once messed up its highly probably that history round circle. So try disable/uninstall MSI Dragon or just start from begining with Windows etc. How To Optimize Win 10 [2004] – Tuning for VR and MUCH more

 

[GaryGavlaar]

Ok..... last night i updated drivers and bios etc on my PC. I've stuck the 3070ti back in, changed the setting for AC in nvidia settings to "prefer Maximum power" as per @RasmusP comment in another thread, and i feel its def performing a bit better now. Got 24 cars on track and its only dropping to 45 when the cars wizz past me.

However the weird thing is my MAIN_T is only at about 75ish, and my graphics card now seems to not be being fully utilised all the time. Now from info further up, if i understand it correct, if the GFX card isn't 95% then its being limited by something else, but also from the information further up, if its been limited by the CPU should i not expect my MAIN_T to be in the 90% region also?

Cheers

 

[pattikins]

Ok..... last night i updated drivers and bios etc on my PC. I've stuck the 3070ti back in, changed the setting for AC in nvidia settings to "prefer Maximum power" as per @RasmusP comment in another thread, and i feel its def performing a bit better now. Got 24 cars on track and its only dropping to 45 when the cars wizz past me.

However the weird thing is my MAIN_T is only at about 75ish, and my graphics card now seems to not be being fully utilised all the time. Now from info further up, if i understand it correct, if the GFX card isn't 95% then its being limited by something else, but also from the information further up, if its been limited by the CPU should i not expect my MAIN_T to be in the 90% region also?

Cheers

There's a lot of confusion of what the MAIN_T does/is - see Stefano Cassilo's explanation.

In AC, are you using mods, for instance, SOL & CSP? Also, are you using any AC apps, as well as 3rd party ones, whilst running the game? Whilst troubleshooting what's holding your game back, I would recommend turning off any mods/apps, including any post-processing.

 

[RasmusP]

Ok..... last night i updated drivers and bios etc on my PC. I've stuck the 3070ti back in, changed the setting for AC in nvidia settings to "prefer Maximum power" as per @RasmusP comment in another thread, and i feel its def performing a bit better now. Got 24 cars on track and its only dropping to 45 when the cars wizz past me.

However the weird thing is my MAIN_T is only at about 75ish, and my graphics card now seems to not be being fully utilised all the time. Now from info further up, if i understand it correct, if the GFX card isn't 95% then its being limited by something else, but also from the information further up, if its been limited by the CPU should i not expect my MAIN_T to be in the 90% region also?

Cheers

If the main_t is very high, it can become a problem. But as pattkins says, it's only "time spent inside the game code" VS overall frame time. So not really the cpu usage or a cpu limit.

You can however look at the colored lines at the bottom, below the main_t value.
Blue = cpu frame time
Red = GPU frame time

When the blue line is higher than the red line, your cpu is the bottleneck.
If the red line is above the blue line, the limit is your graphics card.

Ofc the limit can also be vsync or fps limiters. For example:
90 fps = 11.11 ms between each frame
CPU time = 9 ms
GPU time = 8 ms
So in theory you could get more fps, but your vr headset is limiting to 90 fps.

Now your cpu time slows down to 15 ms.
That's longer than 11.11 ms so your headset drops to 45 fps.
45 fps = 22.22 ms between frames so you have a lot of performance headroom now.

Your cpu has 22.22-15 = 7.22 ms headroom
Your GPU has 14.22 ms headroom

Now your utilizations will show a lot lower values. In percent:
Graphics card:
Frame time = 8 ms
Fps limit at 45 fps = 22.22 ms

8 ms out of 22.22 ms = 36% "GPU load"

The same will happen to your CPU.
Load percentages are just the results of how long the hardware was doing something within a specific amount of time.


Additionally:
And hardware can only do something at full performance or not. So 50% load is not like a human being working with only half of it's capabilities.
It's pushing your body to the maximum and then sitting down for the same amount of time
Electronics can only "do" or "not do". You can however tune their speed with voltage and clockspeed.
Which is why at lower clock speeds, you will see higher "load %" while playing the same scene.

 

[GaryGavlaar]

You can however look at the colored lines at the bottom, below the main_t value.
Blue = cpu frame time
Red = GPU frame time

When the blue line is higher than the red line, your cpu is the bottleneck.
If the red line is above the blue line, the limit is your graphics card.

Ok .. just gone and tested this.

When on a flat screen i'm getting about 110 to 130 fps depending on location of other cars (lower when they are in view etc)... but the Blue line is constantly above the red, so my cpu is stopping any higher FPS in that instance?

In VR though (don't know how to get a screenshot when in VR), i also get the blue line above the red but sitting at a solid 90fps, however when i all of a sudden get drastic drops to 45fps (when cars come back round) the red line jumps up to be level with the blue line (blue line stays where it is), then sharp back down again and fps goes back to a solid 90...... is this still my CPU bottlenecking in this scenario, or is the GPU experiencing some kind of quick overload that's causing the drop?

EDIT ---- I notice my PHY is high compared to other screenshots in this thread too :/

 

[GaryGavlaar]

There's a lot of confusion of what the MAIN_T does/is - see Stefano Cassilo's explanation.

In AC, are you using mods, for instance, SOL & CSP? Also, are you using any AC apps, as well as 3rd party ones, whilst running the game? Whilst troubleshooting what's holding your game back, I would recommend turning off any mods/apps, including any post-processing.

Hi Mate,

Yes mods in use, but removing them didn't seem to make any difference to what i was experiencing, which is what had initially made me think that there was a bottleneck elsewhere other than my GPU. I will run more testing this eve, but at the mo i'm trying to keep everything consistent so don't want to change too much compared to what conditions ive used for comparison tests.r

 

[pattikins]

Hi Mate,

Yes mods in use, but removing them didn't seem to make any difference to what i was experiencing, which is what had initially made me think that there was a bottleneck elsewhere other than my GPU. I will run more testing this eve, but at the mo i'm trying to keep everything consistent so don't want to change too much compared to what conditions ive used for comparison tests.r

Looking @ the screenshot of your Task Manager (#23) - indicating that your system is using 8% of your cpu whilst 'idle', coupled with the mods & whatever settings you've got AC @, I'd suggest that you've overloaded your cpu.

Try doing the 'race' test again with afterburner running in the background - in VR or 2D. I think you will find that one or two threads are running maxed out. Have you tried running the default benchmark? These are the results of my previous setup (AMD 3600X & 1080ti that also struggled with a full grid!):
AC VERSION: 1.16.3 (x64)
POINTS: 44939
FPS: AVG=306 MIN=140 MAX=454 VARIANCE=34 CPU=85%

LOADING TIME: 12s
GPU: NVIDIA GeForce GTX 1080 Ti (2560x1440)
OS-Version: 6.2.9200 () 0x300-0x1
CPU CORES: 12
FULLSCREEN: ON
AA:2X AF:8X SHDW:2048 BLUR:0
WORLD DETAIL: 5 SMOKE:3
PP: QLT:3 HDR:0 FXAA:1 GLR:3 DOF:3 RAYS:1 HEAT:1

 

[GaryGavlaar]

Ok, so the 5800x CPU is now in, and there is a definite improvement. It looks like the GPU is now my bottleneck, with it running maxed out.

Last night i was quite reliably holding 90fps with a 24 AI car grid, apart from i seemed to get some quite big drops when teh time cycle moved into darkness, which i presume is down to more lighting effects and shadows etc...

 

[RasmusP]

Ok, so the 5800x CPU is now in, and there is a definite improvement. It looks like the GPU is now my bottleneck, with it running maxed out.

Last night i was quite reliably holding 90fps with a 24 AI car grid, apart from i seemed to get some quite big drops when teh time cycle moved into darkness, which i presume is down to more lighting effects and shadows etc...

Nice to hear!
The 3xxx Ryzen's were a great improvement over the 2xxx Ryzen but they lacked some single thread performance compared to the 8th/9th/10th gen Intels.
The 5xxx Ryzen are now showing Intel how it feels to lack in that area

The time cycle changes are not only "transition to darkness and more shadows etc". It's changing stuff in the game.
Remember, it's just SOL + CSP, which are basically "hacked into the original AC".
Superb work from Peter, Ilja and the rest of the people who are involved. But some performance hits when the lighting is changing has to be expected.

Maybe you can fine tune your CSP settings to get rid of the fps drops. But probably you can't.

 

[GaryGavlaar]

Nice to hear!
The 3xxx Ryzen's were a great improvement over the 2xxx Ryzen but they lacked some single thread performance compared to the 8th/9th/10th gen Intels.
The 5xxx Ryzen are now showing Intel how it feels to lack in that area

The time cycle changes are not only "transition to darkness and more shadows etc". It's changing stuff in the game.
Remember, it's just SOL + CSP, which are basically "hacked into the original AC".
Superb work from Peter, Ilja and the rest of the people who are involved. But some performance hits when the lighting is changing has to be expected.

Maybe you can fine tune your CSP settings to get rid of the fps drops. But probably you can't.

Yeah i dont think its anything to do with SOL or CSP as i unchecked the Post Processing option and think I had the same issue if i remember right.

Hey, I barely do any night racing, and i'm running at 1.5x super sampling, so it looks lovely. I'm happy, and can confirm for anyone else reading this, no matter what GPU you have, the CPU is in issue in this game.
I will continue to tune and test and see if i can improve or work out exactly what's happening, but for now i'm in a good place

 

[RasmusP]

Yeah i dont think its anything to do with SOL or CSP as i unchecked the Post Processing option and think I had the same issue if i remember right.

The night transition is done via the Weather FX and Lighting FX extesion of CSP. And in the Weather FX settings, the "Controller script" is normally SOL.
Disabling Post Processing won't stop the SOL Controller Script to change to "dark mode" for the night.
If you disable weather FX and Lighting FX, you won't have any night racing anymore. It will stop transitioning at 18:00 o'clock.

I'm happy, and can confirm for anyone else reading this, no matter what GPU you have, the CPU is in issue in this game.

Yep, this is a good summary! I always recommend to get the fastest 6-core CPU one can get for simracing. More cores aren't needed for simracing but the single thread performance is super important for everything!
You can always just buy a better GPU, open your case, take the old one out and throw the new one in. Easy peasy! (Not since Covid with the GPU problems...).

But upgrading the CPU often includes a new motherboard, faster ram, taking ALL cables out etc.

So I would always go for a great CPU and upgrade the GPU depending on the budget or simply lower settings.
If your CPU is struggling though... You have to lower all settings A LOT to get enough fps in simracing.

 

[GaryGavlaar]

The night transition is done via the Weather FX and Lighting FX extesion of CSP. And in the Weather FX settings, the "Controller script" is normally SOL.
Disabling Post Processing won't stop the SOL Controller Script to change to "dark mode" for the night.
If you disable weather FX and Lighting FX, you won't have any night racing anymore. It will stop transitioning at 18:00 o'clock.

Ahh that makes sense! Every day is a school day.

You @RasmusP, are a legend! We need more people like you on forums!!

Cheers for all your help.

 

[javiersm100]

Noooooooooooooooooooooooo its ended.................... what happened. Its like a TV series that gets axxed! Come back, tell us the end of the story!

Hi mate sorry for the cliff hanger I switched to ACC and now my VR problems are other
Want to get back to AC but have no time. Lets see...
By the way I switched to Quest 2 too and looks that 72fps are more affordable for my rig.