If you can't get DLSS4 working automatically, or via DLSS override in the Nvidia App, then this guide is for you!
Step by step:
MSFS2020: It *might* be possible to do everything via the Nvidia App.
MSFS2024: Need to use Nvidia Profile Inspector.
1. Download and install latest NVidia driver
2. Download and install the new NVidia app (not strictly necessary with MSFS2024)
3. Restart PC
4. Start the Nvidia App, select MSFS2020, and ensure that DLSS override - Model presets is set to 'frame generation - latest'
5. Download the latest version of Nvidia Inspector
6. Important: delete the CustomSettingNames.xml if present in Nvidia Profile Inspector folder
7. Run it and change the settings as per the instructions below
8. Enable DLSS indicator to check that DLSS4 is working: https://easyupload.io/m/n2drlz
9. Start the sim - check that DLSS4 is active by looking at the DLSS indicator overlay
10. Disable the DLSS indicator
Run Nvidia Profile Inspector as an administrator and, in the Global Profile, set 0x00000001 for the following settings:
Enable DLSS-FG override
Enable DLSS-SR override
Enable DLSS-RR override
Set 0x00FFFFFF for the following settings:
Override DLSS-RR preset
Override DLSS-SR presets
Click Apply changes in the top right corner to confirm the changes.
Download the latest Nvidia driver here:
https://www.nvidia.com/en-us/geforce/drivers/
Download Nvidia Profile Inspector here:
https://github.com/Orbmu2k/nvidiaProfileInspector/releases/download/2.4.0.8/nvidiaProfileInspector.zip
Download DLSS indicator here:
https://easyupload.io/m/n2drlz
Digital Foundry deep-dive videos:
https://www.youtube.com/@DigitalFoundry
Note: I'm using MSFS2024 SU1 beta.