Yeah, weird... My laptop shuts down. No warning... No errors... No BSOD. Then restarts on its own... No errors... Like nothing has happened.
 
Time to get a new one?

disable the auto reboot so you can see what the bsod is... but, yeah, it could be that time

Heat (overheating) can cause that.  Common on laptops.  No warning, no BSOD notice (it isn't a BSOD), etc.  
 
You can try cleaning it, as laptops have minimal fan speed/cooling and can collect dust. 
 
 

pwalpwal
disable the auto reboot

Thanks
 
How do I do that?
 
And, like I said, there is no BSOD. Are you saying that there may be a BSOD once I disable auto reboot.
 
Sorry to sound like a noob... I am a shadow of my former self.
 
Also, just to elaborate, both shutdowns/restarts this morning happened while I wasn't actually doing anything. So I can't even replicate the problem.
 
 
cheers, and thanks again,
 
andy

Follow these steps to disable the Automatically restart option:
In Windows, search for and open View advanced system settings.
Click Settings in the Startup and Recovery section. ...
Remove the check mark next to Automatically restart under System Failure, then click OK. ...
Restart the computer.

 

and check event log, there should be something in there
 

Windows event logs may have the details.

Start... Mmc.. File... Add remove snap in
Event viewer
Windows logs

Big thanks Peeps...
 
Just taking all this in.
 
About ten seconds after my previous post my mate knocked on the door and I left my laptop streaming some SoundCloud stuff.
 
Two hours later... Get back to my laptop and it's still merrily streaming away...
 
I'll look at some stuff and come back.
 
cheers
 
andy