Windows 10 Dell Laptop Unexpected Shutdown. Not Overheating.

My partner's laptop running 1803 Win 10 pro has recently been shutting down whilst watching Youtube. It occasionally happens every few days.
When it is rebooted it automatically opens the Chrome browser on the page from which it turned off.
Doesn't seem to be a heat problem. No temperature above 62 degrees C.
Any thoughts?
s.

 

My first thought is still heat. While 62°C is not too hot for the CPU, there are other heat sensitive components inside the notebook that could be over heating. So I would start by opening all the access covers, remove all removable devices (battery, drives, etc.) and try to blast out as much dust as possible.

Consider a notebook cooling pad. Just make sure it comes with its own power source instead of relying on power from the notebook's USB port. No need to put further strain on the system.

 

Thank you Digerati, The laptop has been using a cooling pad for a couple of years now.
What surprises me is that it remembers the web site last visited when it is turned back on.
It's not a big problem.
s.