i have vram issues that when sometimes the vram is 2gb higher then the session before. Really weird
I don’t know if it’s VRAM, but I’m having significant issues with fps suddenly and inexplicably dropping to 1, 2 or 3fps. I can do an entire flight at 100-120fps, and then be about to touch down and crash the plane because the rendering virtually comes to a halt. I’m running a 9080 CPU and 5080 gfx card, clean installation, and no mods or anything running in the background.
I run on an RTX 2070 Super (and I79700k) on 4K and high-ultra settings (with frame gen) and no problem (50-90 fps).
I have the ASUS 5080 and no problems… this is 80 FPS with a 7950 from this AM… RENO to SFO.
Maybe turn off multiplayer… no help and make sure no apps in background.
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I think I’ve fixed it - or my issue at least, and it involved learning something fundamental and new about Windows (which given I’ve worked in IT for 22 years was a surprise!).
In Windows Settings under System→Display→Graphics, you can choose which graphics hardware each application uses. By default they choose it themselves. I’m wondering if Flight Sim, in conjunction with Windows, was deciding to use onboard motherboard graphics at times, thus the 1-2fps moments. I switched it to my graphics card for all my games, and haven’t had a problem since - I now run at the usual high fps all the time. What led me to this was the fact that when I get the fps problems, my graphics card fans weren’t spinning up, which on my silent PC was fairly obvious when it happened. In moments of low fps I’d expect an overloaded graphics card, not an underloaded one….
What confuses me (and I’d be interested to know if anyone can explain this to me) is how this would even work. My monitors are connected to my graphics card outputs, not the motherboard. Is the motherboard (CPU? Or is there a dedicated graphics chip on it?) capable of generating graphics and then passing them to my graphics card to use its outputs, somehow bypassing the GPU and VRAM and going straight to the outputs? Or does it partly use the graphics card in some way?
Either way - it’s fixed. This was all a month ago now and it’s been fine since.
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That is very odd, presumably some sort of weird Windows bug getting confused about what is doing what. The internal GPU is part of the CPU, feeding the motherboard graphics port. I can’t see how it could possibly feed graphics to the outputs of your graphics card.
I would think that disabling the internal graphics in the BIOS would give you the same effect.
Incidentally, on my machine Flight Simulator doesn’t appear in the list of apps under System-Display-Graphics. I could add it, but I don’t want to in case it breaks anything. I did also note that you can set ‘Optimisations for windows games’ on and off by app in there too, there has been another suggestion that having that set to Off makes a difference to 2024, even though the option makes no difference to a DX12 application.
The easiest way to avoid that issue is to disable the onboard graphics in the bios. I forgot to do that once and noticed there were two display adapters in device manager, even though I only had my graphics card plugged to a monitor. Disabling the onboard graphics in the bios removes it from Windows.
I really hope this brings some level of performance improvement
Man, you’re a LIFESAVER. I’m playing in 4K on a 16GB VRAM card and whenever I started running out of memory and the shared VRAM started going over around 3GB, not only the sim was slowing down to a halt but it never recovered the shared memory until you restarted the sim - so a VRAM-heavy departure airport would screw up the whole flight all the way to a sim restart.
Changing this Windows setting did some kind of sorcery (I’m in IT too and I also have no clue how that was even related) because now I can not only go all the way up to several gigs of shared memory without killing the performance (it introduces some minor stutters but no 1-2FPS slowdowns) but it properly recovers this memory whenever you get up in the air. Thank you, now I can FINALLY enjoy the SU4 benefits to the fullest!
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Yeah that’s called a memory leak
Yes, you are right. You can also see this move in GPU-Z.
No worries - glad I could help. It’s super weird and makes no sense to me, as I always saw onboard motherboard graphics as redundant on PCs fitted with graphics cards, just like onboard sound is for those of us with soundcards (although I wish someone would tell NVidia that, as they keep selecting onboard sound when they run updates on my gfx card!). But yes, since changing that setting in Windows, FS has run beautifully for me. Strangely, a friend of mine has an almost identical PC spec and hasn’t ever had the issue, so perhaps it’s the BIOS setting mentioned on this thread? (see RogueNaught’s post).
I’m still curious as to how this works. My GFX card fan wasn’t spinning at all during the low fps moments (my You Tube vid confirms this, as it was taken on a phone pointing at the screen), so that would be consistent with the idea that the motherboard takes over graphics sometimes.
If you’re not using the motherboard’s onboard graphics, you should disable it in the bios. That way Windows would not even be aware of it.
I recently tried to make a flight from miami to dallas y in the PMDG 777F, initially all went well, i used the latin vfr miami with FSTL traffic, I had 80-90 FPS at taxing and take off. At cruise altitude entering texas form the gulf my FPS tanked to teens and single digit numbers and GPU usage went to 100%, I was not near any major cities and there werent many clouds near. This issue had happened before just after touchdown in another airport but at cruise altitude it was very un expected. My settings are mostly High and only clouds are ultra. My system is a ryzen 7 9800 x3d and RTX 4070 super. I presume this problem is the famous VRAM bug I thought they would get fixed with SU4, at this moment the 777 is unusable, this has also happened on touch down with the citation X. I am lost at what to do.
What is your texture resolution and tlod at? (and screen resolution)?