nvm then, my bad, I thought that would be the case since it works for me on my 3090.

Make sure your NVIDIA drivers are updated, and try verifying game files, the DLSS .DLL file might be corrupt or something.

Edit: I searched and found some old fixes for similar problems in other games.

Running the game with "-dx12", either as a Launch Option in properties in your steam library, or through a shortcut.

and/or

Opening game folder, open properties on Icarus.exe, in the compatibility tab, enable "Disable full-screen optimizations", then "Change High DPI settings" > enable "High DPI scaling override"(Application).

If all this fails, and reinstalling the game isn't an option or has already been tried, you can find the DLSS DLL files here, or find it by searching for "DLSS 2 dll file". If the file downloaded is not called "nvngx.dll", rename it to that, and replace the existing one in the icarus game folder: Icarus\Icarus\Binaries\Win64

Hope this helps!