Windows 10: games working fine for 10 mins but suddenly the frames drop to 10

i dont know why but whenever i play games for 5-10 mins it works fine and my cpu and disk give it sufficient power to run but after 10 mins suddenly my cpu and disk drop to 5-6% and frame suddenly drops to 10 fps i tried checking if it is a overheat issue and no it is not basically after 10 mins of playing cpu and disk stop giving the game the power needed.

:)

 

Game frame drop

When I play a game for 20 minutes or less, my frame rate drops to 1-10 fps and I have to restart the game. I'm not sure what's causing this (counter strike global offensive)

 

Low cpu usage and sudden frame drops in games

I tried all of the above things, even reinstalled the game but still problem persists. Game works fine for like 5min but then frame drops start again.

 

Frames dropping suddenly.

So I played some games yesterday on my surface pro 4 and the frames were from 30-60. The next day later it dropped all the way to 1-20. I had tried:

Cleaning the disk

Removing unimportant files

Definitely not overheating

The games would work so well but now its crappy??? Can some please help me, Thanks.