So, the problem started a few months ago and after months of research I couldn't find the solution. I'm asking now for an advice before I go to a proper Apple service. The computer restarts sometimes after boot. When Apple logo appears, it just automatically restarts and then it boots normally. The curious part is that when I boot to Windows via bootcamp, it boots normally. So, I have been using mostly Windows these last few months. I nearly forgot about this, but I'm worried now because a new problem arrived: After shutting down, both OS X and Windows, the computer turns itself back on. This also happens only sometimes. What does this look like to you? Is it hardware or software problem? I plan on replacing the HDD with SSD. Do you think this will help?