"Change the prefs. İni file in your documents/users/mygames/fallout4 and in your steamapps/common/fallout4 to the following,
Bmaximizewindow=1.
Bborderless=1.
Bfull screen=0.
İsize h=1080.
İsize W=1920.
If you dont want 1920/1080 resolution replace with your own.
I was able to run Fallout 4 perfectly in Full screen with this fix.
Hope it helps!"
Buyurun link.
This will run fallout 4 in fullscreen: Change the prefs.ini file in your documents/users/mygames/fallout4 and in your steamapps/common/fallout4 to the following, bMaximizeWindow=1 bBorderless=1