- While running the game unmodded, FPS reaches high values but remains visually choppy, as if it's running at 60 Hz.
- In my case, installing Stutter Remover (v4.1.36) did the trick.
I'm also running downgraded version of the game (v1.7.0.3) and experimental FOSE (v1.3 b2).
Now, for some reason the solution of using Stutter Remover was edited out and removed in 2019, referring to it not being supported by W10. I'm currenting running W10 21H2 and can confirm it working. Do recommend restoring 'hackable' status.
Alternatively, there are also "Fallout 3 Tick Fix" and "lStewieAl's Tweaks".