For some reason that happens at Frys quite a bit for me. The thermal pad is a double sided sticky, it was OK at first but I knocked the board loose dicking around inside and since then not much in the way of stickiness, but have some thicker spares. I want to somewhat sleeve the ATX cable so I'll be in there one more time.
The ATX spec says 12V +/- 5% so 11.4V/12.6V, right now max load it maybe goes down to 12.6V but normally something around 12.7-12.8V. I'm not worried about it though, it's high by 7-8% if it was 10% or more I'd be sending it back.
How does it compare to the pico box psu (200W) you have? Or does the pico box psu not have enough grunt to power the cpu + gpu?