Laptop auto shutdown

[Bjsheng]

I'm using Lenovo G40. Recently when I adjust my lid it has chances to just shut down itself without anything prior error... It also happens when I try to play games on my laptop. What is the problem that will cause above problems? It's not overheating, at least not when I touch the bottom after it shutdown

 

[velo3100]

It could be the screen is not connected properly causing it to switch off. A way to check if it is overheating is to use hwinfo monitor to check the cpu and gpu. If it hits 90 or more then its overheating.