the effected rig has been updated with the recent w10 update. Revert back to the previous driver should get the rig back to normal again.
Do you know if the Nvidia users are also affected by this update? Because I have nvidia card in my computer with which I do mining occasionally, but I have not notice any irregularities when it comes to hash rate.
Maybe it would be better to revert to previous update, and not to wait the moment when this problem starts appearing?