I recently bought a new 5K iMac 27 inch, I proceeded to restore it from my time machine backup, and then I proceeded to install a couple things onto it to get it up to speed. The only problem was about 10 minutes into using the machine, it randomly restarted on its own. There was no error message or warning, it just restarted itself on its own. Is this something I should be worried about? It hasn't done it since. I'm a little concerned. Thank you!