Recently my R9 Fury has been under clocking itself to about 950mhz instead of 1050mhz. The clocks fluctuate a lot and there doesn't seem to be a reason for it. Heat is not the problem because i custom water cooled my Fury and it stays in the mid 70's to very low 80's under full load. My temperature limit is set to 85C and i never had the under clocking problems in the past. I'm pretty sure it is a driver issue.
GPU- R9 Fury Nitro
RAM- 16gb of corsair vengeance lpx @ 2666mhz
MB- AsRock z170 extreme 6
PSU- Be Quiet! Straight Power 10 650W