Anyone else getting random stutters accompanied by loud desktop fans?

[Ihavenoclue]

Pretty much title. I don't have this issue with any other game plus I updated my GPU which is an RTX 4090, as for CPU I have an Intel i9-13900KF. Not seeing anyone talk about this but I hope it's a game issue.

[Treant]

We are playing the game on 2 different machines
and noticed that there are areas within the game,
where both of us have exactly 45 FPS (instead of 60).

Some areas will also rapidly switch between 45 and 60.
Does not feel like the usual stutter you get when hardware is too slow.
But rather like game is switching between 45 FPS lock and then back to 60 FPS lock.

And yes, I can confirm that CPU load is indeed very high,
but with high render distance and all those moving objects,
it can be expected to be CPU heavy game ... (not well optimized right now, tho)