I know there is an actual low FPS / stuttering issue, but the problem I’ve occurs since I’ve the Sim (begin of January). So I tried really a lot of different stuff.
So that is, what my CPU usage looks like:
So as you see, Thread 3 has a usage of around 50% and cores 5 to 8 are alternating at 100% (only one thread at one time, NEVER 2 at the same time)
And that, what it looks like in the sim:
So as you see, that’s 4K, so i thought okay, let’s do another test, turn everything on, use just the default DV20 (needs less CPU Power, and go to a place, somewhere nowhere (no traffic, no photogrammetry etc.)
Even then, there is no difference between 4K and 1080P
So i think, something must be wrong with my CPU (configuration?).
I know, MSFS is quite bad at CPU usage, but that’s quite lower than found in a lot of other forums an especially it uses just 1 to 2 cores at one time
So what system do I use:
Ryzen 5900X (newest Chipset driver)
nVidia RTX 3090 FE
MSI B550 Gaming Carbon (newest BIOS)
2TB nVmE SSD
64GB DDR4 @3600
Sounds like you are always limited by Main Thread? I have nearly the exact same setup: 5900x, 3090, 64gb 3600 mhz. Only my motherboard is different with an MSI x570, which shouldn’t make a difference.
I’m almost always GPU bound, even with the 3090 overclocked and in an airliner. I have to drop from 4k to 1080 before I start seeing limited by main thread. I haven’t had any real performance issues until this latest update where I’m now getting regular and periodic stuttering intervals. They disappear if I drop the Terrain LOD down to 30, which suggests the CPU is being blocked while terrain data is loaded.
Have you tried disabling SMT in the BIOS? I’m wondering if you’re getting throttled somewhere, maybe temps on a single core are too high? Or Windows is trying to do something else on the same core.
Another thread suggested adding a Windows Defender exclusion for FlightSimulator.exe, msmpeng.exe, and the community and official folders as these processes can actually fight for time on the same core. I’m going to try that next to see if it helps some.
Oh yeah, I’m always limited by Main Thread…
SMT is enabled, I’ll try to disable it.
Do you have it disabled?
So cooling should be fine (Cinebench, 100% Allcore is about 70°C).
I even tried to set up my PC completley new (so format everything, Setup Win 10 new, only MSFS installed) same thing…
Since I never got 60 FPS (I mean really never), I don’t think, that it is a Win10 Problem…
What does you CPU Useage look like?.
Regarding your GPU Limit:
As you get exactly 60 FPS, did you have a FPS Limit activated (GSync, VSync or in the nvidia control center)? If I do that, i also get the message, Limited by GPU (but still not 60 FPS ^^)
what you’re seeing in task manager is the CPU shifting the task between different cores (you’ll notice the dips in one graph line up with the peaks in another).
The CPU does this automatically to keep core temperature lower (and thus frequencies higher).
This is completely normal, and nothing to worry about.
If the CPU were to keep the main thread pinned to a single core/thread, this one would quickly heat up and lower clocks.
Yeah, it’s like the Screenshot in the first post. But nevertheless, there must be something wrong, more or less the same system like @SkipTalbot ,but just half the frames ^^
And what is interesting, with SMT off, it does no CPU Shifting (and it also stays cooler).
well, you’re only using half the threads now. So there are no ‘free’ threads available to ‘jump’ to.
CPU usage isn’t ‘better’ in your latest screenshot, it just looks better since you’re only utilizing half the threads.
Whatever is causing the difference between you and @SkipTalbot must be a setting, driver difference, firmware difference or something like that. Maybe you have the panel refresh rate on high, and he’s got it on medium? (that one is pretty CPU intensive).
in your first screenshot you see 4 threads (that’s 2 cores) working with the peaks and valleys, in your latest shot there are 2 threads (also 2 cores) maxed out. See, they’re both fully working 2 cores, only in the 1st picture it’s shifting the load between threads.
You say that you’re not running any traffic or live players, yet I see a purple plane on the left side of your screenshot. Have AI traffic on?
Hm, I’ve to try it again (but I think tomorrow, it’s nearly 2 AM here ^^), but as i observed it, i’s shifting between the 4 Threads (so there are never 2 on peak, just one at a time so only one core, but I’ll check again with SMT ON).
Thas must be an parking aircaft:
Sorry for the German settings, that means Traffic OFF
One more thing to check tomorrow; while the sim is streaming and processing photogrammetry data, that eats up a lot of CPU resources as well. Maybe Skip was already fully processed on the scenery. Maybe run a test with photogrammetry disabled as well, to rule out that variable.
Thanks also for you, and even thank you, for trying to help
Hm, that’s true and yes, it’s on (of ocurse, i want to look it good, but just give me a moment).
hmz, last thing I can think of for now is doublecheck that your RAM is using the XMP/DOCP profile in your BIOS.
Ryzen loves fast RAM, and if you’re running it at 2133MHz, that might well cause a performance drop.
I’m looking at your FPS captures. Your GPU is pushing over 50 FPS, right? Are you thinking that FPS isn’t high enough? What are you seeing while flying? Poor quality graphics?
The FPS counter shows a lot of green and some yellow… Nothing red or dark red that I can see. Your CPU processors look fine…
BTW “limited by main thread” only means the GPU isn’t a bottleneck. It means something outside the GPU is limiting the main thread. Could be hardware, software, network, or maybe Windows virus scan. It could be watching YouTube. The FPS counter cannot provide any additional information about what is limiting the main thread. Some assume that MSFS is single threaded or is not coded correctly for multiple processors. That is NOT what the FPS counter is saying.
So you’re right, with SMT On it’s also using 2 cores( 1 Core/2 Threads alternating 100% / 0 %, the other one alternating 25% / 75%, that’s why only one thread is maxed). Nevertheless, SMT Off gains around 5 FPS.
XMP is enabled and RAM is running at 1800/3600 MHz (also double checked with HWInfo).
I’m very Happy with my GPU, and yes 50 FPS would be more than enugh But if you read, that’s somwhere nowhere with a DV20. When I’m sitting in an Airliner FPS are going below 20 sometimes. Limited by CPU. And no, that’s not enough (and as you can see on the other Screenshot, it shows deep red)
Even it if it would be enough, it is very strange, that @SkipTalbot get’s 60FPS with nearly the same HW (just other Mainboard). So sth must be wrong with my config.
I know that MainThread just means, not the GPU, an I never stated, it’s the MSFS fault (or did I?). I just want to know what’s wrong with MY configuration, so I also think it’s not MSFS fault, but there must be some point in my system, not working as intended. That’s what i want to find out. Because if it’s my system, MSFS improvements wouldn’t help me
So to sum up, what did I try yet:
Set up a complete new Win10 and installed just MSFS on the system without anything in the Community Folder
Disable/Enable SMT
Updated all Drivers and Firmware (Including BIOS of MB)
Excluded MSFS exe and all the folders from Defender
Turned Off ALL Online Serivices in MSFS
Tried different resolutions from 1080P to 4K
In all cases i got the same CPU Usage and more or less the same FPS limited by MainThread (whatever it may cause)
(and as you can see on the other Screenshot, it shows deep red)
