Help, very weird fps drops in races.

Can somebody help me with this?

When driving races in AC framerates drop from my normal (locked) 90 FPS to under 30.

I am not running vsync or freesync.

As you can see in the image my GPU is only running around 35% here while when driving solo or running benchmark it runs at 99% with unlocked framerate.

Nor is my CPU bottlenecking, all cores run at max 60%.

I do not have this in other sims.

PS: It might still have to do with AI, No difference between 6 or 30 opponents...Games runs smooth with 97% GPU usage....IF I am in pole position or starting last. When in the middle of the pack GPU usage drops a lot, as does the FPS. But the CPU does not get above 60% so thats not a bottleneck. Weird...weird....weird...
AC framerate issue.jpg
 
why do you use the x16
This ->
nvidia AF looks better than AC's AF. The AC AF was very taxing at x16 but the nvidia x16 is okay for me :)
why do you use Nvidia inspector
I see you also use compatibility 0x00
The compatibility bits are all nvidia default. Didn't change them :)
I use the inspector to get access to Sparse Grid Supersampling (sgssaa). It's not available from the normal nvidia control panel.
And after setting compatibility bits and different Anti Aliasing methods for a lot of games in the past, I simply always use the inspector. It's just quicker to access and I have a better overview :)
Noticed you include the forced on V-sync, knowing we have a similar monitor, I just limit my fps to 119 and have v-sync off.
https://www.blurbusters.com/gsync/gsync101-input-lag-tests-and-settings/15/#
Second point about V-Sync.
In short and simple words:
If your fps drop, the monitor will lower its Hz in sync. But if the fps go up again, the GPU won't wait for the monitor to finish its current frame. You will get a very slight tearing at the bottom of the monitor. However that's basically invisible, it might seem like a little stuttering.

So gsync = monitor and gpu are synced and during fps drops, the monitor will wait for the GPU to finish the current frames and go down with its Hz accordingly.
V-sync forced on too = GPU will wait for the monitor to finish the displaying of the current frame before sending in the next one.

BTW you should limit the fps to 117, not 119. Every fps limiter has some hiccups and if that hiccup gets too close to 120 you will either get input lag from vsync kicking in or get tearing/stuttering because gsync shuts off.
Also for me, once gsync shuts off it needs about a second to get working flawlessly again.
Also i use LOD bias clamped, notice you do not.
Yeah that's a topic that gets me triggered a lot.
All guides still state you should put it to clamped but in reality nvidia simply BROKE that feature at some point a few years ago. I think the GTX 5xx series was the last gen that had this setting working.
Nvidia doesn't say anything about this but there are petitions going on.
There was some guy that hacked the drivers to get the CLAMP back but sadly he stopped doing it at some point.

In short: don't bother about clamp or not, it doesn't matter at all, it's simply broken and we have to live with all the awful pixel shimmering at distant objects.
 
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Bloody hell, I feel such a noob, you guys have way more know how about GPU's and their settings then I do...I basicly have everything thats not done in game on default. I have the feeling there is way more I could get out of my GPU using all these extra options in nvidia control panel,inspector, etc. I just lack the knowledge, but also lack the time (and patience:rolleyes:) to read up in all the forums and tutorials. What also makes me hesitant is the million people, million opions factor. Sometimes very it is hard to know who to believe as a lot a people just shout someting without really knowing whats what (mostly even with best intentions!) Clearly that is the case here :). The last thing that makes it hard for me is that I always forget what I changed and how I did it so I then end up f...cking up my whole system and getting very anxious:confused::confused::laugh:.
 
Bloody hell, I feel such a noob, you guys have way more know how about GPU's and their settings then I do...I basicly have everything thats not done in game on default. I have the feeling there is way more I could get out of my GPU using all these extra options in nvidia control panel,inspector, etc. I just lack the knowledge, but also lack the time (and patience:rolleyes:) to read up in all the forums and tutorials. What also makes me hesitant is the million people, million opions factor. Sometimes very it is hard to know who to believe as a lot a people just shout someting without really knowing whats what (mostly even with best intentions!) Clearly that is the case here :). The last thing that makes it hard for me is that I always forget what I changed and how I did it so I then end up f...cking up my whole system and getting very anxious:confused::confused::laugh:.
Totally agree. I've read a million guides about the Logitech g25/27 especially for AC.
In the end I created my own settings from scratch but I think I hit the nail with them.
Generally at least during the last 2 years I only state things that I'm very sure about really knowing what I'm doing there.
The internet is full of random not working crap because almost nobody really tests them in a structured way.

What I do: I love snipping tool and paint!
When I'm configuring a game I create a txt file and a new folder.
Then I note down everything I'm testing and do Screenshots either via snipping tool or "print" and ctrl+v into paint and give the Screenshot a name.

Configured a lot of games for hours and weeks over the last years. After forgetting half of it and becoming unsure about what's what I began to create a structure.

Good thing about this: coming back after a few years I can still configure it swiftly :)

Regarding my inspector settings:
Don't go into it yet. The main things there are:
- Using Nvidia vsync rather than ac's vsync
- 2 pre rendered frames (lower is better but 2 is smoother on the cpu)
- I have gsync, so there's something special and different to most about fps limiting
- I force sgssaa
- I use the Nvidia anisotropic filtering

You don't really need anything of this though :) I merely did it for completion...
 
What I do: I love snipping tool and paint!
When I'm configuring a game I create a txt file and a new folder.
Then I note down everything I'm testing and do Screenshots either via snipping tool or "print" and ctrl+v into paint and give the Screenshot a name.

Configured a lot of games for hours and weeks over the last years. After forgetting half of it and becoming unsure about what's what I began to create a structure.

Good thing about this: coming back after a few years I can still configure it swiftly :)

Regarding my inspector settings:
Don't go into it yet. The main things there are:
- Using Nvidia vsync rather than ac's vsync
- 2 pre rendered frames (lower is better but 2 is smoother on the cpu)
- I have gsync, so there's something special and different to most about fps limiting
- I force sgssaa
- I use the Nvidia anisotropic filtering

You don't really need anything of this though :) I merely did it for completion...

Great tips and suggestions! Thanks for that!
 
Regarding my inspector settings:
Don't go into it yet. The main things there are:
- Using Nvidia vsync rather than ac's vsync
- 2 pre rendered frames (lower is better but 2 is smoother on the cpu)
- I have gsync, so there's something special and different to most about fps limiting
- I force sgssaa
- I use the Nvidia anisotropic filtering

You don't really need anything of this though :) I merely did it for completion...

Where do I find SGSSAA? Only in inspector or also in nvidia control settings? And what is it? lol
 
Where do I find SGSSAA? Only in inspector or also in nvidia control settings? And what is it? lol
Only in inspector, yes.
It's sparse grid supersampling.
The story behind it is quite fun. It's only what I read about it though:
Nvidia screwed up the supersampling once but everyone loved the results so it stayed.

It works a little bit differently compared to normal supersampling. The filtering algorithm is a bit different and the result is a bit blurry but also extremely smooth.
So if a game allows for it I use sgssaa and use a bit of reshade's lumasharpen.

The biggest difference in general between msaa and supersampling is that foliage and transparent stuff gets smoothed too.

See for yourself in the video: (YouTube Bitrate is too low to make fxaa and msaa really flicker)
 
I might as well ask in this thread rather than start a new one.

I hadn't raced for a couple of weeks and in that time there was an Oculus update, I also updated CSP and SOL. I've been getting freezes of like 0.5 - 2seconds once or twice a lap since then, I tried reverting back to CSP version 140 and SOL version 1.2x but it hasn't helped. I'm even getting the Oculus hourglass loading symbol flash up during the freezes sometimes. I'm wondering if it was the Oculus update that caused my issues or whether it is CSP/SOL. Have any other Oculus users been experiencing issues with the latest Oculus version? AC is pretty undriveable for me as it is right now :(
 

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