To unlock frame rate open Fallout4Pref.ini (located at C:Users[name]DocumentsMy GamesFallout4). Note making a backup isn't neccessary as if you simply delete Fallout4Pref.ini the game will auto generate new one next time it is opened.How do you enable vsync? Tried forcing it via drivers but doesnt work.
Search for the line iPresentInterval=1, and change it to iPresentInterval=0
Keep an eye out on this thread -[Fallout 4] Modding . Mods and discussion within - NeoGAFThere should be good info on mods and other tweaks.