I'm not entirely sure how AMD cards operate but this is standard of NVIDIA cards. If it the display driver crashes, clocks reset back to stock. Most likely your card that is crashing is overclocked to high.
True, AMD cards operates the same and I find it normal.
But in my case AMD allways resets: reset, power failure, etc.
To make it simple: if I install Windows 10, drivers, run Claymore with my clocks and reset the rig, after reboot the driver ignores my clocks/voltages.