Are you using the latest bios?I know both components are good as I have tested them in different configurations. However, together all I is power on and fans spinning and a black screen, no post. Is there any chance the Rx570 will work with this motherboard?
I have reset the CMOS and switched between PEG and IGD, as well as UEFI and UEFI+Legacy. The only time I got action with the RX570 installed was with IGD set and using VGA out on the motherboard; however, it locked up within seconds. On PEG there is no output out of the ports on the GPU or the ports on the motherboard.Could it be you disable VGA output by accident? Have you tried clear CMOS?