Sudden Shutdown Predator PH315-51

VitalHD

I have a Predator PH315-51 for about 2 years now and recently my frames are dropping when i play fps games (Predator Sense indicates that i get 90 to 98C when playing). a while ago, it has been shutting down immediately for some reasons (overheating maybe??).

for that, i have some questions i want to ask

what should be the normal CPU temp range depending on some scenarios (gaming, browsing etc.)

should i replace my thermal place? when should my thermal paste be replaced?

how will i check my overheating problem? is overheating really the reason?

whats the best software/tool for verifying it?

there are so many softwares available but im too overwhelm too choose especially with the details given by the software.

GAMING6698

@VitalHD
In all gaming laptops/gaming computer after one year need to clean fans, air vents and need to apply new good quality thermal paste.

And yes, you will face fps drop and sudden shutdown because of high temperature.
90°C or more is not normal and may harm your laptop.
Personally, While playing games my CPU temperature is 77°C max and GPU 67°C max

(Result after cleaning and repasting)

Solution-
Things you need -
1)correct tools to open laptop screws

2)you should buy best quality thermal paste name "thermal grizzly kryonaut" or "Arctic MX-4 2019 edition"
3)Buy isopropyl alcohol 70%+ to remove old thermal paste 
4) use dry cloth(Moisten the cloth with isopropyl alcohol, then rub the chip & sink with the wet cloth. Don't apply the solvent directly on chip because it'll spill over on the board)

If you want best temperature while gaming then follow these steps one by one-

(opening back cover is really hard so be careful, you can watch some youtube videos also)

First you need to clean laptop fans and air vents before applying new thermal paste 
Follow this video-

After cleaning fans, air vents don't assamble heat sink/cooling system.
First remove old thermal paste from both GPU/CPU chips and from heat sink.

After removing old thermal paste you should apply new thermal paste on both chips(use spread ing method)
Now, assamble your cooling system/heat sink after applying thermal paste
You can see spreading method from below video-

Note- After assambling don't open heat sink again, if open then you will introduce air pockets when putting it back on because the way the paste was separated. This causes trouble when dissipating heat and can possibly damage your CPU.