Macos 10.15.5 update caused kernel panics for owners of many Radeon Navi cards. Your card have to be POSTed (aka inited) at system boot to hit this issue. So if you use flashed card on MacPro5,1 or you use the card in hackintosh (init is done by UEFI) then you might hit it pretty well It could easily be fixed, you need to downgrade just one kext (kernel extension) to make things working again Firs