"Issue seems to be with NOP v4.10, it maxes out a single core on the .NET core process. It does not appear to be multi-threaded." - my team
(PS: Running server 2008.)
https://www.nopcommerce.com/boards/t/56033/cpu-over-usage-nop-41.aspx
The dll used to fix is from here for reference of other people who have this issue and for Nop team.