I really don't know what to call this game... its a hot mess. I don't think the lag and stuttering will ever disappear; I experience the same issue on my laptop... reducing graphic settings does not help. Turning game mode on doesn't completely get rid of the lag and stuttering. So sad because Payback is a fun game, its just the lag and stuttering that has prevented me from fully enjoying the game. Some people say this is a Windows 10 Fall Creators Update issue, so I am not too sure.
I have tried closing everything before running the game - I still get the lag. I cant downgrade to Windows 8 because my laptop came with Windows 10.
Frostbite just doesn't work well with racing games... similar is seen with Need For Speed Rivals on PC.