If you are using an nVidia graphics card it may be running off of your CPU rather than your GPU.
I went into the nVidia control panel-> manage 3d settings-> program settings-> then added HellDivers-> then selected for the High-performance NVIDIA processor.
These are some suggestions from other users who managed to solve their graphics card selection issues:
- Go into the graphics settings after you load the game. Turn everything to lowest setting or off. Turn the vsync off. Turn the fxaa thing off. Etc etc. Then exit the game and go to the nvidia control panel and select the game and choose the nvidia card. Then for good measure under the global settings force every game to run nvidia as well. When I loaded up the game after doing all of these things it finally selected the nvidia card and runs way better.
Chances are it was likely a bug in one of the in game graphics settings that was preventing me from selecting my nvidia card.
- Deinstall your graphics driver (control panel -> programs -> uninstall -> nvidia graphics driver) and everything else graphics related. Then do a clean install of your video card driver. This fixed it for me and I can now rightfully select the preferred graphics processor with nvidia actually listening to the setting.