Hm I have the same issue, when putting my pc in hibernate, once it's powered down inmediatly it powers up again? I coudn't figure out what the problem was.. so I kinda lived with it. The weird thing though is that it doens't always happen, and not always the same time, sometimes it takes about 20/30 seconds to power up again, and sometimes it's inmediatly Perplexed

I would love to know if there's a solution to this vague issue.

btw: I know for sure WOL is not turned on in my network