Microsoft Flight Sim 2024: Best UserCfg.opt for DLSS 4.0

The goal for MSFS 2024 is to balance Frame Generation (FG) with Terrain LOD to prevent the “MainThread” bottleneck ($T_{main}$) while using DLSS to keep the GPU load optimized.

File Path & Setup

1. MS Store: %LocalAppData%\Packages\Microsoft.Limitless_8wekyb3d8bbwe\LocalCache\UserCfg.opt
2. Steam: %AppData%\Roaming\Microsoft Flight Simulator 2024\UserCfg.opt
3. Pro Tip: In 2026, the UserCfg.opt file features a dedicated DLSS section. Ensure Hardware Accelerated GPU Scheduling (HAGS) is enabled in Windows 11 settings, or the Frame Generation options will not initialize.

Optimized “Aviator Ultra” Configuration Table

Parameter	Recommended Value	Technical Purpose
SecondaryScaling	1.000000	Keeps internal resolution native for DLSS to upscale effectively.
Terrain.LoDFactor	4.000000	Overrides the UI limit of 2.0 (200) for crisper long-range terrain.
Sharpen	0	Disables engine sharpening to let DLSS 4.0’s native logic handle clarity.
Raytracing	1	Enables hardware-accelerated shadows (requires DLSS 4.0 to maintain FPS).
DLSSMode	1	Sets DLSS to “Quality” mode (requires UI confirmation).

{Video
	Adapter "NVIDIA GeForce RTX 5090"
	Monitor 0
	Windowed 0
	Fullscreen 1
	Resolution 3840 2160
	...
}
{Graphics
	Version 1.1.0
	Preset Custom
	{PostProcess
		Enabled 1
		EyeAdaptation 1
		ColorGrading 1
		Sharpen 0
		Fringe 0
		LensDistortion 0
		Dirt 0
		Upscaling DLSS
		SecondaryScaling 1.000000
		DLSSMode 1
		DLSSFrameGen 1
	}
	{Terrain
		LoDFactor 4.000000
	}
	{ObjectsLoD
		LoDFactor 2.500000
	}
}

HowTo: Engineering the DLSS 4.0 Experience

Follow these GameEngineer.net technical steps to ensure your simulator runs with “Zero-Stutter” precision:

1. DLSS Swapper (Manual Update): MSFS 2024 often ships with an older nvngx_dlss.dll. Use the DLSS Swapper tool to force version 310.x.x (DLSS 4.0) into the game directory. This significantly reduces “ghosting” on glass cockpit displays and propeller edges.
2. The LoD Balancing Act: Setting LoDFactor to 4.0 or higher provides incredible mountain detail, but it hammers the MainThread. If your FPS becomes “choppy” despite high averages, reduce this to 3.0.
3. Secondary Scaling Tip: If you are playing in VR, set SecondaryScalingVR to 1.200000. This renders the initial image at a higher resolution before DLSS downscales it, making cockpit gauges readable even in “Performance” mode.
4. Reflex for MSFS: Ensure bNvidiaReflex=True is active in the .opt or UI. Because Frame Generation adds a small amount of latency, Reflex is mandatory to keep the aircraft controls feeling “direct” rather than “floaty.”
5. VRAM Management: For RTX 40/50 series users, set VideoMemoryScale to 0.85 or 0.90. MSFS 2024 streams massive amounts of data; giving the OS 10–15% breathing room prevents “DirectX Device Hung” errors during long-haul flights.

Technical Explanation: Multi-Frame Generation ($FG_{multi}$)

In 2026, DLSS 4.0 introduces Multi-Frame Generation. Unlike DLSS 3 which generated one frame between two real frames, DLSS 4 can generate up to three ($3\times$ Override).

By setting an in-game cap of $45\text{ FPS}$ and using $3\times$ Frame Gen, your display receives a buttery smooth $135\text{ FPS}$. This is crucial for flight sims because it allows the CPU to spend its “time budget” ($T_{budget} \approx 22\text{ms}$) on complex flight physics and AI traffic, while the GPU uses AI to maintain the visual fluidity. This results in a “Flat Frametime Bar,” which is the secret to a stutter-free landing.