So, you can select dldsr in Nvidia control panel, it’s by looking for dynamic super resolution and set to 1.78x check box. This is located under global settings in Nvidia control panel. Then you can select a higher resolution in windows display settings. This will give you 1440p reloution. Another way is to select custom resolution in Nvidia control panel and select 2560x1440 progressive and click test. After you click test, you need to then set the correct resolution in windows.
This should also set the correct 1440p display. Then you can either leave your desktop at 1080p and just set msfs to 1440p in the resolution section of the settings or you can select both desktop and msfs to the same resolution.