Clevo W860CU - graphic failure or something else?

After a few weeks I can again be on my laptop. I experienced a problem, and before shipping the laptop back to the store, I want to be sure, what to do.

The story goes like this.

I use the laptop every day, sometimes it's on even longer. When I used it and switched it off, the next day I could not start it up. I tried and checked various things.
Nothing helped. After a week, of leaving the laptop alone, I switched it on again. It was working fine for a couple of days. On another day, it...

Clevo W860CU - graphic failure or something else?

Clevo W860CU - graphic failure or something else?