I would just shut it down manually wait for a couple of minutes, start it again and it would work properly until the next unexpected shutdown. It would do this thing of shutting down, starting up again and before anything would show on the screen shut down again and be stuck in some kind of a loop like this. So I cleaned it, got rid of all the dust, put everything back on and after 30-45 minutes it still shutted down. First I thought it was overheating, the laptop is kind of a 'gaming'-ish laptop, it was made in such way that you have easy access to the motherboard and all the components, RAM, HDD, CPU, the heatsink and fan.

I googled this stuff a little bit, it was just so frustrating as it always happened at random intervals and never had a clue about it. So since 1-2 weeks or so my laptop started doing some random shutdowns.