You're probably know about it, but both Bitcoin Core 22.0 and Windows 7 are outdated. I would recommend you to both of them.


Looking at https://github.com/bitcoin/bitcoin/blob/v22.0/src/init.cpp, looks like only -par=1 only can be used to limit total core/thread used by Bitcoin Core 22.0. Besides that, try setting bitcoin-qt.exe to have lower CPU priority using this guide https://answers.microsoft.com/en-us/windows/forum/all/how-to-permanently-set-priority-processes-using/df82bd40-ce52-4b84-af34-4d93da17d079.