Interesting, because I also have a similar problem. The eternal Supermikro startup screen, “System initializing” on the bottom left and “B7” on the right. It is also impossible to enter the bios. I bought a used board and there was already a Windows on it, I couldn't download a new one from a flash drive, so I downloaded “gparted-live-1-7-0” via IPMI and uninstalled everything through it, then installed “windows_server_version_1909_x64_dvd” but I didn't like it, so I uninstalled it again with “gparted-live-1-7-0” after which the eternal boot began. I reset the bios by removing the battery, also updated it via IPMI, it does not help