My Sapphire R9 390X is having this problem too currently.
The situation is almost same ( Windows 10 64Bit )
In beginning I always got the message of "Display driver amdkmdap stopped responding and has successfully recovered." in event logs.
It keep crashing when I'm playing ARK
Do you have Raptr and AMD's gaming app installed? I was getting a black screen and sound freezes playing CS:GO and Source. It also started happening when the action got heavy so I thought maybe it was lack of cooling, tho probably not. This was on a dual Sapphire 390x setup. I also noticed that the time was off whenever I'd boot and read in a separate forum that this might have been the culprit so I manually set the time on Win10. I removed Raptr and AMD app, removed the driver utility and re-downloaded the driver utility thru Sapphire. They also have a button that sets the graphics card to run UEFI vs Legacy so I set it to UEFI, not sure if that helped but it seems stable. Oh, and check to see if MSI has a utility to shut off ULPS on the card itself. I think there is an issue with Win10 and the 390x when more power is needed for the cards fans to spin. Hopefully this will help you out too kye923.