I'm get about 8 reboots a day, let's say, to give a frequency to this. Mostly when I've opened a bunch of stuff am am using it "heavily", but once it was just sitting there "doing nothing".
And to jah25, I get double-boots and shutdown-reboots too. It's not a feature - it's supposed to stay off! I assume that it just triggers whatever's bad while it's shutting down and so reboots at that point.