Edit 2: Update on the explanation for this section down below

Edit: I'd like to update my findings on this topic. I loaded my backup BIOS settings with all cores enabled and overclocked p-cores and e-cores. The fps drops were back. I can varify it in the first tunnel, with drops to 45fps and even 30 fps when leaving the tunnel. I disabled e-cores again and the fps drops were gone.

I did not want to have all apps running on p-cores, so I was looking for a solution having e-cores enabled and I think I found it, at least no fps drops for 15 minutes straight and the tunnel works fine on 60 fps.

Fix:
1. When the game is running, open task manager
2. click on Enshrouded.exe and go to details
3. Right click enshouded.exe under details and select cpu affiny from the menu. This is where you can decide which cores are used to run the game
4. Select all CPU on the top and press OK
5. Game now runs fine for me

Some more explanations/info on this. Here is where it gets strange. I have P-Cores on index 0-7 and E-Cores on index 8-11 (according to CPUID HWMonitor). If I enable only Cores 8-11 then I get 12 fps anywhere in the game (slow lane E-cores only). So that works as intended. If I only select cores 0-7, The performance is somewhat okayish, but still some drops to 50 fps, with the major drop to 30fps at the tunnel exit still hitting me down to 45 fps. And if I enable the top setting "Use all cores", it works flawlessly.

I checked other apps currently running and they all have "Use all cores" checked. BUT! When I first went to change the affinity for Enshrouded, this was not checked. only cores 0-16 were checked, and my list goes up to 19. I have no idea what 12-19 is, seriously. But checking "use all cores" did the trick. Somehow my Win 10 thought it was okay to not default to this setting for enshrouded

___________Correction to this
I thought CPU 8-11 would be e-cores, but i was wrong. Cores 0-15 are my logical processors for my 8 p-cores. CPU 16-19 are my e-cores. One can check by looking at the task manage graph view, switching it to logical processors. Enabling use one single e-core (15-19) in the affinity will fix the fps problem. But using all of them works even better. Using only the e-cores 15-19 will increase its usage to 60% maximum. Using none will still see some usage causing fps drops. Using a combination of at least 4 logical processors and 1 e-core will also give good fps, but not great fps, depending on the power of the cores it seems. using enough p-cores with at least one e-core will work. using all of them will work too, obviously.


___________ Old post below

I had massive frame drops, especially on dedicated servers. Only on my local saves it was somewhat passable playing on balanced with a cap of 60 fps via Nvidia Control Panel. On servers it was insane, drops to 10fps every couple steps. Here is how I fixed it:

1. Disable your E-cores
2. ~~Disable your CPU overclocking~~
3. Limit fps to 60 in Nvidia Control Panel

Some info: I only intended to disable e-cores, but it also automatically disabled my OC settings, pushing it down from 4.9 Ghz (which was tried and tested for the last two years with benchmarks etc.) to stock 3.6Ghz. I only noticed because of a popup I got when saying bios settings, but I just went for it. Now I have buttery smooth 60fps on balanced with no fps drops whatsoever. I can actually enter the first tunnel on servers without getting to 8 fps or something.

As for the NVidia setting: Use it because the internal refresh rate seems to be capped (look at known issues thread) and this helps smoothing out the game and helps with using the selection wheel when building.

I dont know if it was the e-cores or the overclocking, not testing it, Im enjoying the game now. Never change a running system :D