Drop in FPS from 45 to 10 - no apparent reason - 4090 rtx, vive pro 2

User Support Hub Virtual Reality (VR)
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I love flying in VR. I did several months without issues. Until now:

On my machine (Win 11, 4090 RTX, SteamVR, Vive Pro 2) I had - after installation of Minecraft a drop in FPS in the Flight Simulator afterwards. I had a quite stable 45 FPS in most sceneries on my Vive Pro 2, set to 90Hz and roughly 3700x3700. Minecraft - maybe just coincidence, it made use of openXR in VR. Edit: Without VR, SteamVR not running, i do have a stable 60 FPS anywhere.

Any Ideas?

What i tried already:
Uninstalling and reinstalling separate OpenXR (until I figured out SteamVR has its own OpenXR, now kept it uninstalled) in the newest (but same) version
Uninstalling and reinstalling SteamVR
Applying for SteamVR Beta for newer Versions
Uninstalling and reinstalling Vive Software
Updating NVidia Driver (this wasnt the newest but didnt change a thing)
Settings in MSFS are the same (some Ultra, Some High, DLSS, etc), compared via Screenshots
Settings in NVidia are still the same - also compared via Screenshots to previous - no specific MSFS settings there
Played a bit with the few SteamVR settings and Vive Settings (more or less all resolution/refresh rate related)

Nothing helped.

The only clue I have: The load on GPU and CPU is ridicliously low, like 9% or so on GPU, task manager says.
FPS counter in MSFS tells it is both limited by Main Thread or GPU (switches every second).

Any Ideas? Especially - why is my CPU/GPU load so low and how to I get it to be fully used?

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Is this drop in FPS constant, aka always present?

If yes, maybe, the install of minecraft messed with some VR runtimes, though not very likely. But anyway, I suggest to check if the versions of the OpenXR runtime and the steamVR runtime changed.

I rember that there was a steamVR update (for me at least) last week.

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thank you for your answer.

The FPS have a few moments where they get up to 20, but mostly stay around like 6..10. For example, Google Earth VR runs smooth at 90fps with 4000x4000 (i know, not as demanding as msfs, but still..).

OpenXR runtime i will re-check, but since i reinstalled all, i don’t assume this could be outdated.

Minecraft - not sure if this was the cause, i didn’t check directly before and after. But i noted Minecraft VR was a bit annoying since OpenXR wanted to open itself. So - i will re-check the runtime versions.

About the SteamVR update - yes i had an older version - so it didnt update right away - but with the newer version, same problem.

The strangest thing about it is: Why is the GPU at just 9%, where it was before more like 90%; same with CPU load. Without VR, everything is super smooth.

Edit/add on info: The “fake VR” in msfs dev mode has high FPS, no issue here.

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hmm that indeed sound strange.

@GPU utilization: how high is the CPU utilization at the same time? Maybe there is somewhere a SW hickup which makes the CPU wait for something and thus the GPU is underutilized. Just a wild guess :face_with_diagonal_mouth: …

But I for myself would still continue to investigate the VR runtime situation. Since you said, that in 2D mode all works as intended, I assume that there is not a general problem with MSFS or your system - it seems that particularly VR has a problem.

Maybe really OpenXR is the culprit :thinking: - but recheck versions in the first place…

Another thing: also check the settings in OpenXR/SteamVR, perhaps something got messed up there. (Render resolution, SSW, etc. pp., …)

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Thank you very much for your answer, again.

Yes I assume the same. It can’t really be 4090/Driver related, nor MSFS 2D-related because the problem does not show up on the flat screen. Driver update didn’t change.
Also it does not appear in other games.
It must be sth with SteamVR/OpenXR. Render resolution and settings i did check. But still maybe some versioning of OpenXR.

These my thoughts (too).

But - I SOLVED it maybe: I did a system restore to some days ago. Everything smooth again. As GPT4 tells me, the system restore does probably not apply to OpenXR nor SteamVR, I am still in the mist what caused this problem. Some Windows Settings? Would explain the strange few-%-load on CPU and GPU.

Anyways I am totally happy it works again, because MSFS without VR is like walking with one leg.

Thank you for your help, @WildTapestry269 - I will closely monitor update here if the problem appears again and if so what caused to unfold it again.

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Ah perfect that it works again. :+1:

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I figured out it was fpsVR. As soon as I started it again, the FPS dropped dramatically. Ending it - all fine. Great tool, sad it is buggy in my case (current version 2.1.8714 and 2.1.8710 same problem).

So, anyone facing the same problem, try to end fpsVR (i.e. via Steam Interface or manually), and see if it helps.

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