When you get this sorted you may want to go to the Asus site and update your Bios, (if needed), as there are some issues with this MB when resuming from sleep. It just might stop this happening again.
The link is to the Asus forum, it will take you to your MB page, you can find downloads there.
Hope this helps, good luck and post your results, thanks.
ASUSTeK Computer Inc.-Forum-