Poor MainThread times in MSFS 2024

vike001141 · August 24, 2025, 9:19am

Hello.

However, with all the flights I do, there’s a really strange bug with performance where my mainthread averages at around 30 ms at whatever graphics settings I choose. It’s like there’s something wrong with the game as it almost doesn’t matter what settings I have, it gives me 2-3 FPS more at best. The problem is bound to MSFS 2024 as I can run other high intensity simulation games (The Bus, SimRail, TSW5) on max settings and get well above 3x of the FPS I get in MSFS 2024. I have tried using DLSS, but that worsens frame times even more. It feels like the thread time is being limited in some way and it’s really getting on my nerves. Does anyone know what the issue might be?

Thermal throttling is not the case as temps are rather cool for running this game (60 on CPU, 50 on GPU.

I have tried stopping all other programs that have some CPU usage (iCUE, Discord, Steam etc.) little to no change.

Specs and other relevant information

Computer Specs

CPU: AMD Ryzen 7 7800X3D

GPU: Nvidia RTX 5070Ti OC Version

Motherboard: ASUS ROG STRIX B650E-F GAMING WIFI

RAM: Corsair Vengeance 32GB DDR5 6400 (running at 6200)

PSU: Corsair RM850X

Peripherals:

Keyboard + Mouse

Thrustmaster TCA Captain Pack

Drivers and software

GPU: Nvidia Game Ready 577.0

Chipset Drivers: AMD Version 7.06.02.123

MSFS Version: Release Version (Xbox)

Screenshot with Ultra preset

Screenshot with Low-end Preset

Screenshot from CapFrameX in regards of Frametime

If anyone could tell me what the issue might be, I would be forever grateful as the poor performance in game is making the experience almost unbearable.

Thanks

Vike001141

tempestornado23 · August 24, 2025, 10:54am

See the many posts in the thread about SU3 performance where a bug has been logged about the mainthread time being very high and rising over time which tanks the fps. No solution has been identified yet but some users can replicate the problem by opening the EFB (showing the map or using the weight/balance, etc). You could try using the EFB and then not using the EFB (so never open it while in flight) and see if your results are impacted. The fact that you lowered settings from ultra to low and saw no difference is problematic and does indicate something else is running in the background that wasn’t there in SU2 which is similar to the other posts in the bug thread.

MrFuzzy1337 · August 24, 2025, 10:58am

Same behavior here, even at low settings with a high end PC. No feedback from Asobo.

OldpondGL · August 24, 2025, 11:23am

The only solution I have ever found is being GPU bound. The GPU acts as a governor to set the timing of the entire sim. When you are CPU bound, the CPU will firehose the GPU with frame commands. Limit the frame rate to 40, load up the GPU until you get around 20ms frame times, then CPU frame times will drop to a constant 10ms-ish.

Babu’s guide is useful.

Here are my stats. This is 2024, but SteamVR reports it as 2020.

I use Medium or lower settings. Note the high resolution. For 2D, use TAA with the render scale slider to INCREASE your resolution until you get GPU bound.

Turn off Nvidia Reflex or Low Latency mode. You don’t need frame generation or quadviews.

I set the resolution in the VR headset, and OpenXR manages my frames to 40 since it determines I can’t reach 80. This would be equivalent to increasing the monitor resolution with a frame cap.

This approach consumes a lot of VRAM, so simmers with 8GB or less may not be able to achieve a GPU bound state.

Note I use DLSS Quality because I set the resolution in the Headset. Turn off any AI related settings.