Engine Multithreading

Hello, guys.

So for the last few days I`ve been playing POE without any problems.

And today suddenly I hear my fan going crazy like never before, in task manager
I saw that poe was taking upto 70% of cpu when it normally takes not more that 20-23%.

I saw a post from last year where someone said that engine multithreading was causing
this issue. I`ve turned it off and bam - 50% cpu usage and back to the normal values of 20%.

So my question is - how was I able to play poe normally last few days and suddenly the game decided to take additional 50% of the cpu ? Switching off multithreading seemed to fix the issue but also my fps drops from 200 to 80 when I switch it off.

I havent changed a single thing on my pc in the last days, any ideas?

(i7 - 7700HQ, 16gb ram, GeForce GTX 1050 Ti)