Random reboots with lollipop topic

I started having random reboots yesterday and I can't for the life of me understand why. I'm running stock 5.0.1 with root and I flashed the factory image with wipe option when I got my N5. I can be randomly browsing Tapatalk or chrome beta or whatever and it just randomly restarts.

Any idea why? I'm out of ideas.

Sent from my Nexus 5 using Tapatalk