I plugin two monitor using rx580, one port is dp port , worked as fine connecting to LG UK650 4k, the other port using dvi port and connect DELL 1080p monitor , this one is dark.
my boot params:
liludump=60 -raddvi -uia_exclude_ss -uia_include=HS03,HS08 -wegdbg -liludbgall
system log...