Black screen means generally two things, RAM or CPU issue, according to Asus specs which you can find it [https://www.asrock.com/mb/AMD/X570%20Pro4/|here], your MoBo is not compatible with Ryzen first-generation, also make sure that you haven’t installed the wrong BIOS on your MoBo, and the last thing to try is to use only one RAM instead of two or more, switch it between all the memory slots and don’t forget to clean the slots with a compressor air.
Remove your graphic card while testing and don’t use it until your system works fine.