Hi Luxus.
It is a bit strange, but I tried exactly the same, but still had the shutdown problem, I sent the MB back to where it had come from , they tested it and returned it to me as not being faulty, this I do not believe, but as it took a few weeks to do all of
this, so I purchased another MB, set it up and all has been great since.
So you may well have a point Luxus, I must try this other NB again some time as it is sitting in the corner at the present gathering dust.
You may well have hit the nail on the head. Glad to hear all is now sorted.
In closing I will add that one must make sure the MB is 64bit compatable and made for Windows8 or you are due for trouble straight away.
Well done Sir.
cheers