Running into the same issue myself.
Have 6 RX 580s. Plugged in one by one, backed up original bios, flashed a modded one. All good. Started the system with all 6 connected, everything ran fine for about 2 hours before i turned off the PC. The next morning when I boot, Windows will only give BSOD at login. Same like OP.
Primary video source is onboard graphics.
Plugged in one by one to debug, turned out when I had this card connected will only BSOD when trying to load the driver.
Things I've tried:
Booted in safe mode, ddu all drivers.
Booted back in windows, can see the card in device manager, but if I try to install the driver it will throw a bsod during installation (system thread exception not handled, atikdmag.sys)
Given that I can see the card even though the driver is not installed, run AtiWinFlash again and flashed the original bios. Still BSOD when trying to install the driver.
Changed risers, still nothing.
Don't know what else to try.