But chips can become heat sensitive. Did the tech give the internals a good clean and do the fans work like new?
If all that is done then it's usually a new motherboard to be installed.
How old? How about a Web Speccy?
Read how at https://www.piriform.com/docs/speccy/using-speccy/publishing-a-speccy-profile-to-the-web
I have a MSI GP70 Laptop that was as having shutdown issues. Took it in to diagnose, tech said it was a bad stick of Ram, replaced it and said it was good to go.
Got it home and my wife tried to start using MS Word and after less than 30 minutes it Shutdown.
Checked CPU and GPU temp which seemed fine.
Could it be something else, multiple issues?
Any help, advice, etc appreciated?