Assetto Corsa Low CPU and GPU usage (1 Viewer)

Dama_The_Crow

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I have noticed that only in online racing I have low FPS (below 90 btw), but in solo race or quick race (with bots) it is 90.

Last night after Norisring I saw afterburner graph and my CPU usage was cca 30-40%, and GPU usage was cca 50%.

Does anyone knows what causes that?

My vertical sync is off, I hve no limiter on FPS count.... I even noticed that FPS is same when i turned on SS to 2.0 or 1.5, with AA 2x or 8x....
 

cheekyspam

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Sounds like a CPU bottleneck. It might be typical behaviour but there might be something we can do.

First a few questions.

What operating system, how do you rate your computer knowledge/ability?

What CPU do you have? how many cores? hyperthread on? How much ram?

Also do you know how many cores your network card is using (RSS - Receive Side Scaling)?

What other software is running when using Assetto Corsa?
 
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Dama_The_Crow

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1. Windows 10 64 bit / 8/10
2. i7 6700K 4cores (8 logical) / hiperthreading ON / 16 GB
3. I don't know ( it is motherboard lan adapter Asus maximus VIII ranger)
4. Steam, OTT, Geforce experience, Asus Xonar audio center, MSI Afterburner, Corsair Link, Teamspeak and Assetto Corsa launcher.
 

cheekyspam

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Sweet specs.

With my 4 physical core (no hyperthread) i5 6600k o.c. to 4.2 and GTX1060 6gb I get 90-95fps on the grid and 115 during the race with 30+ cars. I get 130+ FPS with 24 cars. All of it CPU limited, smoke and shadows are on low in settings.

When you look at averages and get 30-40% on multi-core is typical usage in a few of scenarios
1. Too much is being "thrown" at the CPU and it can not sort it in time so the cores are under used.
2. Not all cores are being used, 40% of 8 cores is 80% of the 4 actual cores.
3. There is a rogue process causing havoc (I had paint go crazy and running all the time after a Windows 10 update but did not show up on CPU usage)

So try a few things and if they don't work we can look further to see if we can improve it.

In game use Mugello with the 38 pit box option and 38 cars, I have found this matches online's performance and turn on the render stats in game app, this will show the CPU usage.

Try one at a time.

- make sure your power setting is set to High performance, anything less allows cores to be "parked" (put to sleep). They will keep turning themselves off and on.
- run the ingame benchmark to see FPS and average CPU usage, this probable won't max out your CPU but if it does???
- limit the FPS in game settings. This will stop the game throwing so much at the CPU.
- Turn off all none essential apps, in game and in Windows. This will see if an app is causing this.
- Turn off Hyperthreading. AC has very poor multi-core support and is even worse for Hyperthreading, it has been suggested it can confuse the game.
- this one is off topic but make sure/change the network adapter to use only 2 cores. In the Network adapter settings in the driver in device manager change the RSS option in advanced to 2.
my network adapter was set to use all 4 cores and I was getting "poor performance". I changed it to 2 and it removed this bottle neck.

See if any of this helps first and we can then take it from there.

If you need advice on how to do any of the above let me know.
 

Dama_The_Crow

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Thank you very much, I'll try that.
 

Dama_The_Crow

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I found problem.
It is not related to PC hardware. I was the apps onscreen. Almost every app, except sidekick, Race essentials, helicorsa and pitlane p.

When I turn on for example FPS counter ingame, fps drops from 90 to 50. Same with realtime positions, or global positions box.

I even raised SS to 2x (later lowered it to 1.5) MSAA to 4x, and still round 90 with 25 cars in race, except in start when I have 80 FPS.
Really strange situation. ...

Settings ac.jpg
 

Dama_The_Crow

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Update:

I turned off now yellow, and red bar in sidekick, and some more stuff that I don't need, and turned on Relative times, and it stayed at 90 (85 with 30 cars on start).
 

cheekyspam

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Interesting, if you turn of SS completely what FPS do you get?
 

Dama_The_Crow

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Last night I set SS to 1 and get some FPS, but not that much (Start 30 cars about 70-85 first lap - 90 later). Then I set SS to 2, and get about 65 on start with 30 cars. All this with Realtime app off. When I turn on Realtime app, FPS sinks to 55 on start, later it is better.

So I found sweetspot: SS 1.5 (didn't notice that much difference in VR picture quality between 1.5 and 2.0 SS), MSAA 4x, World High, Smoke minimum, Reflection static (I can turn reflections to dynamic but with 20-30 cars, but I lose 10 FPS, and reflections is not important in VR), filter quality High, Glare High....
With this setting, I have on start 30 cars, about 75 to 85 (varying), and after 1st lap 87-90 with 90 lock later in race.

All this with just Sidekick app, and Realtime app to turn on when is necessary.

Now waiting for race.
 

Spybee007

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Last night I set SS to 1 and get some FPS, but not that much (Start 30 cars about 70-85 first lap - 90 later). Then I set SS to 2, and get about 65 on start with 30 cars. All this with Realtime app off. When I turn on Realtime app, FPS sinks to 55 on start, later it is better.

So I found sweetspot: SS 1.5 (didn't notice that much difference in VR picture quality between 1.5 and 2.0 SS), MSAA 4x, World High, Smoke minimum, Reflection static (I can turn reflections to dynamic but with 20-30 cars, but I lose 10 FPS, and reflections is not important in VR), filter quality High, Glare High....
With this setting, I have on start 30 cars, about 75 to 85 (varying), and after 1st lap 87-90 with 90 lock later in race.

All this with just Sidekick app, and Realtime app to turn on when is necessary.

Now waiting for race.
I know this is over a year later, but thanks so much. This totally helped me figure out why my FPS was suffering in VR. Running AC with Sol on an Oculus Rift S, 32gb ram, 3900x and 2080 super and ASW was constantly on. Turned down all settings and still couldn’t maintain 80 FPS. Found this and turned off all my apps in game ( I have a bunch ) and like Magic it’s running 80 FPS constantly with 1.5 SS, 8x MSAA and sol is configured at high settings.
 

Aman-Droid

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Hi another user reporting Success in VR. I disabled Steam's motion reprojection (like oculus's ASW) just so that i could see the live framerate.
My max framerate was around 70fps in an offline session on brands hatch with 4 AI cars.

I did the following:
- AC > options > general > UI modules > Disabled all apps except Chat & G Meter
- Then in game I turned off Render stats app and turned off the Realtime app
And I just used my monitor to view the FPS as my nvidia software normally shows it, or you can use fraps etc...

And it shows that now im back to 90FPS :cool:

Just saved myself £100s in upgrades hahaha!

My Specs:
Windows Mixed Reality VR Headset
Intel i7 3770
12gb dual channel ram
GTX 1050 TI 4GB
Windows 10

Take care!
 

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