On the contrary, <i>all</i> popular physics engines today (including the one in FO4) do not tie simulation framerate to rendering framerate. <i>That</i> would make the simulation incredibly unstable. Instead, the physics happen in their own thread at a fixed timestep. It&#x27;s up to the game developer to have enough sense to write non-blocking multi threaded code, but if they do things by the book everything just works. This includes FO4, which contrary to your post does not have a 30 FPS cap (except on consoles).