When watching movies or browsing in Youtube sometimes picture freezes and then restarts by itself, i wonder if anyone got same issue, last night watching 2 hour movie and got 3 restarts, maybe its lack of cooling i dont know.
Artur from Estonia 
Anker Nebula Mars 3 restarts by itself randomly
I may be able to diagnose the issues if you answer these questions.
Does it get hot?
Does your battery drain quickly?
How old is it?