My amount of used VRAM increases while my available VRAM decreases — FPS drops, stutters, etc

User Support Hub Install, Performance & Graphics
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Hello everyone,
I’m facing a serious issue that I just can’t get rid of…

For some time now, with any aircraft (Fenix, PMDG, iFly, etc.), I’ve noticed that when I depart from the airport, everything runs smoothly and perfectly fine. In Developer Mode, I can see that I’m using around 7–8 GB out of the 16 GB on my RX 9070 XT (first part of screenshot).

The flight goes smoothly at first, but after a while I start noticing a drop in FPS. In Developer Mode, as soon as my VRAM usage goes above 9 GB, the available VRAM suddenly drops to 13 GB, as you can see in the second screenshot.

And when I land, it becomes a complete disaster. I’m using more than 10 GB of VRAM out of the 11–12 GB available, sometimes even getting dangerously close to the limit, which makes the game unplayable. In the third screenshot you can see this happening, but keep in mind that I’ve already dropped to 20 FPS, with the purple “graphics queue” spiking, and it becomes impossible to play normally.

I’ve tried with ReBAR turned ON and OFF, deleted the rolling cache, cleared the DX cache and my GPU cache, and tried so many other things, but I still can’t find a solution.

Before, with these settings, I was able to fly with a steady 50–60 FPS without excessive VRAM usage. Now it’s impossible, no matter which aircraft or airport I use.

VRAM descent
VRAM descent827×799 171 KB

Do you have any suggestions? I’m exhausted from trying to figure this out — I just want to fly peacefully again.

Thank u so much <3

1 Like
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Is that the same than reported here ?: FPS performance - VRAM bug?

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Hello, unfortunately I don’t have the impression… Unlike the posts in the thread, my ‘available’ VRAM keeps decreasing during the same flight, not theirs.

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Are you by any chance running other apps like a browser? Other apps do use vram but in your case the vram situation still looks ok.

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No, no, I don’t have anything else running in the background, and it’s always the same pattern:

Takeoff and cruise are perfect, but when I start the landing phase, my VRAM usage goes above 9 GB and the available memory drops from 16 GB to 13 GB.

Then once I’m close to the ground, I’m at 11/11 GB almost constantly, and I get a ton of stutters, FPS drops, and so on.

If I start another flight, even in the middle of a desert, my VRAM is maxed out and my FPS are below 20.

And just by restarting the game, boom — I’m back to 70 FPS in the exact same spot.

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Personal Comments and Observations

Can you repro with stock (non Third Party) planes? Right now it seema like the common denominator is third party aircraft use.

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Hello, I’ll try and keep you updated.

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Hello, i just tried with the 330 and i have the same problem :melting_face:

image
image263×350 43.3 KB
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And it seems I’m not the only one… we have the same GPU, a 9070XT.

https://www.avsim.com/forums/topic/679832-my-max-vram-is-going-down-during-flight/page/2/

1 Like
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Try this. With the FPS counter displayed, and Developer mode off, fly end to end without switching views or swapping in and out of Settings. I suspect there’s a memory leak each time you change settings or bounce in and out of the cockpit. Let us know.

1 Like
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Hello,

It seems you were right, I don’t even need to start a full flight. I “played around” by switching views several times, circling around the aircraft, activating the drone camera, etc., and that’s when I saw my FPS drop drastically, going down to barely 20 FPS… Whereas before doing all that, I was at 50–60 without any problem in the same scene…

See this screenshots with same settings ^^’

Before switching view :

before_switch
before_switch2551×1414 204 KB

After switching view :

after_switch
after_switch2550×1400 197 KB

How can I fix this issue? I’m only having this problem on MSFS 2024.

1 Like
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We can’t fix that. It’s up to Asobo to fix the sim. I recall just toggling in and out of VR will cause a CTD. I haven’t tested that lately, but it’s the same cause. Objects get created, and data gets stored, but they don’t get cleaned up properly.

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I see, but why do people on Twitch, YouTube or elsewhere not seem to have this problem? I mean, they manage to complete a flight properly, while for me it’s just impossible.

2 Likes
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These vram overflows occur in very dense photogrammetry areas or large airports, especially with complex airliners

Try “Dynamics settings” ON with a frame target of 30 fps. This helps MSFS recover faster when a VRAM overflow occurs.

And setting Rebar to OFF will reduce the frequency of overflows.

Also, limit the number of other applications you use while running MSFS. They can consume RAM, and some even use VRAM.

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Good question. It’s a very simple test.