Since I have to take this as it's new, you have a warranty issue with the maker.
if this is old, then we do see heat increase with age. It has to do with heatsink compound cracking as it ages and dries along with fans that degrade, dust, dirt and blocked vents.
There are also other factors like case air temp that is driven by room air temp and fans.
Nothing's really new going on here but how to solve is in so many priors. If it's new, it's a warranty issue and you make trouble with maker or builder. If old, you do the usual compound work, clean and such.
As these get years old you may have to change fans, power supplies, motherboards or other parts to get it under control. Nothing wrong with moving to a better heatsink too.
Just after starting the PC, it's getting overheated. If I try to run a game or heavy software the computer is shutting down automatically. I have AMD Fx4100 processors with Gigabyte Motherboard. So what are possible reasons behind this overheat?

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