i played around with these settings right on the first day of the early access, and there is something weird happening. setting the processor count to *far* below actual available physical/logical cores of course reduces performance heavily. however, setting it to somewhat below the actual available cores still may use *all* threads at 100%, which shouldnt happen.
the game seems to use 8 threads, and if one has eg. 8c/16t, it mostly uses the 1st thread of each physical core > 8 threads, while the second remains unused; occasional usage of both threads of a core is most likely due to windows power settings (overutilization > switch to another thread; or even constant duty cycling), however using high/gaming/ultimate performance power plans, or a custom one as i do, actually should prevent this from happening > another indication of an issue if it still happens, except it is due to heat throttling; stuttering may also occur when a task hops from one thread to another, this is why setting the game's worker threads above the actual available threads leads to stuttering or even crashes (task reserved for a non-existing core/thread needs to be queued back to an existing one, and the task currently performed on this one needs to be halted, then the same happens with the next task > microstutter).