Laptop overheating for no reason

[Rishi_P]

I have a hp laptop (HP 15-db0000 laptop) with windows 10 home. I have been able to watch youtube videos smoothly on 720p quality until recently and watch movies on any other streaming sites for like 4 hours nonstop. then some weeks before it started shuttering on yt, just buffering every second even though i have good connection (i tried changing connection but no use and my phone runs fine). i didnt face any issue with any other video watching websites at that time. then after a week or so it began to overheat when watching yt. still no problems on other websites. now it started to buffer & shutter the same way on other sites too. it is overheating the second i start to play anything (gpu temp. shows 87-89 C). fps is soo bad that it feels like im watching a slideshow (i used to get 30-45 fps before). and it just locks itself due to overheating. i can hear the fans screaming even if im on windows store or explorer. i reinstalled windows from usb and removed everything, no use. then i went to near by store and they changed the thermal paste. it is still not resolved. i have no third party apps running in background other than system apps. task manager shows normal readings. i have scanned full system for malwares (used bitdefender free and windows defender). i contacted the store and they are saying to repair the motherboard. what should i do? is there a possibility that task manager is wrong? but why is the fan so loud? pls help. the screenshot is when im typing this. i have this tab open and win defender running. it is sad cuz it used to run minecraft windows edition while watching yt tutorials. any suggestions or help is appreciatedwhen im typing the question