might want to try to redo the paste, recently i did for my old laptop it did boot up fine and and functioning, then after some hour the temp goes up too high and shut down. The fan spin like crazy if try to on it again.

so clean up and redo again, so far temp already stable, only the pch is remaining at 60-70C but i read that it is supposed to be like that so i just leave it at the moment.

The CM mastergel regular has a very hard/dry consistency and quite hard to apply properly especially for seldom diy like me.

the service guy may not have time to test long enough.