How do I determine why my laptop randomly reboots itself?

Solution
Depends on when it does this and what happens before it does it. Does it bluescreen or just reboot with no warning or messages? It's often a motherboard or video chip issue (which is the same as a motherboard issue really on most laptops).

To rule out any software issues you can first install a new Windows setup on the system after backing up your files. If that fixes things, good, if not, you need to start to look at hardware. RAM should be easy to test, maybe try running without the battery for a while. Check if the issue comes up during game or other times when the system is working hard.
Depends on when it does this and what happens before it does it. Does it bluescreen or just reboot with no warning or messages? It's often a motherboard or video chip issue (which is the same as a motherboard issue really on most laptops).

To rule out any software issues you can first install a new Windows setup on the system after backing up your files. If that fixes things, good, if not, you need to start to look at hardware. RAM should be easy to test, maybe try running without the battery for a while. Check if the issue comes up during game or other times when the system is working hard.
 
Solution