5900x CPU usage on Tak Manager

Hey everyone.

So I have this new AMD Ryzen 5900x CPU on a new rig, and I am using Swar’s plot manager to plot on Windows.
I have noticed that as soon as I launch the manager, on the very first job, the CPU usage gets to 100% on task manager, whether I use 2 threads or 4 threads per job.
Although on Swar’s manager’s viewer I only see a max of 45% usage.
CPU’s temp is stable at around 75 degress
On my other rig I have a 3900x and task manager seems to show the correct load, and never reaches 100%.
Would you say it is a windows issue, and it cannot track the CPU load correctly, or there may be an issue with my CPU?
thanks!