AE using 100% CPU with "easy tasks" and slowing down workflow

Hi,

I've recentely changed my GPU from a GTX 780 to a GTX 1070 Ti, switched from Win 7 to Win 10 and upgraded to the new After Effects CC 2019: I hoped that all of this would improve my workflow, but since this happened I find After Effects going slower, in particular my CPU is jumping all the way to 100% usage even with small tasks.

Last day I was working on a still frame that had both a very easy Trapcode Particular snow-like layer and a Camera-Lens Blur effect on the background: i was typing a text, something like "Merry Christmas" and as soon as i started to scale up the text my CPU would go 100%, which was pretty bizzare counting that it wasn't even a Full HD comp.

My CPU is a Intel Core i7 4770k 3,50 ghz quad core: it's almost 5 years old i know, but not that bad to not being able to scale a text .

My RAM  is a dual channel DDR3 16 GB 1600 mhz.

What should i do? I would like to improve both the ram and the cpu, but i don't have the money right now: moreover i wanted to improve my workflow by switching to a new gpu and new software, not slowing it down... Its' really annoying and most importantly feels like something is wrong.

Thanks!