SUdden FPS Drops and HUge Lags in Witcher 3

[Ankit Saiyan]

FX 6300
R9 270x 2GB
G Skill 8GBx2
MB: GA-78LMT-S2 Rev.1.2
WIndows 10

Okay iit started happening last night. Game was running fine on Highest with 30-50 FPS. But now game is lagging alot for some reason I am getting 1-20 FPS

temperatures were fine but when i checked i saw 96 C. I changed the thermal paste and cleaned every dust from it. But today i checked the temperatures were like OMG!..I was checking temperature all the time didn't notice this much...  I mean how can a system be still on while CPU is at 200+ C?
I think my CPU is damaged now.

Temperatures-

It never happened before. Last time I updated my Windows Since then it started happening
Any solution will be appreciated, thanks!

 

[Edit]

2FPS in Assassin's Creed Unity even on the lowest settings. Is it the RAM?
because AC Rouge  is running at 60 FPS. It is only occupying 3 GB of RAM

 

[Edit 2]
I am on a mission in witcher 3 in which game is running smoothly at 40 FPS but all those FPS is driven by graphic card. Average CPU usage is around 10-20. Now CPU is bottlenecking but temperatures are all normal never cross 45