A few days ago I ran a CCleaner scan and clean up and now my computer runs like it's missing half its parts. I thought maybe the frame drops were because of new updates to the games I play but they work fine on my similarly built system. How is it possible this program has dropped the performance of my PC by 80%? What does the "Health Check" delete that's so vital to the computer?
I take it that you are seeing this with games?
There are reports elsewhere that Windows Updates in March and April have caused frame drops/stuttering in games.
It depends on various parts of the system, graphics, settings, etc. which explains why some PCs see it and others don't.
https://windowsreport.com/update-kb4535996-games-micro-stutters/