Question My pc started to have a lot of fps drops in game's that it should run smooth

Aug 29, 2020
I bought my pc 1 month ago piece by piece I started using it it worked smooth until one day I started to get a lot of fps drops in every game (roblox , team fortress 2 , Overwatch , GTA V)
until that happened everything was working fine no fps drops whatsoever. my fps drops happen like this I start the game it works fine for like 10 seconds then 300 to 20 fps for about 5 seconds then that happens over and over. I tried to fix this by : reseting pc (didn't work) , uninstalling games (didn't work) what else could I do about this?
here are my specs :

CPU: Intel(R) Core(TM) i3-9100F CPU @ 3.60GHz
RAM : 8 ram 2666 mhz (only runs at 2400)
GPU: GTX 1650 Rog Strix 4 gb
Windows 10 home edition
a 1 TB HDD
and a 240 gb SSD (for windows)
my display is 1920x1080 60 refresh rate
I also have good cooling with 6 fans