Look at this thread -
Clicky
Had had very similar problems to you a couple of days ago (ASUS board too) - we ended up reinstalling, clearing partitions, formatting and reinstalling - with only one drive attached.
He also did the above too - so may have been a combination of things - but ultimately fixed. Read the thread and do assess what may apply to you. It would seem like the latest Windows update was the problem.
The only other thing that i added was to only have critical updates applied - and when installing Windows have internet disabled and drivers ready to install (if you go down this route).
Any questions - if you choose to do this - just ask...
*I would edit your posts into one until a reply, otherwise the mods will give you a little slap