Zen 3 on X470D4U causing lockups

Ahoy ahoy friends.

Recently i have purchased an ASRock Rack X470D4U Motherboard, running with a Ryzen 2700X.

I have upgraded my workstation, using an ASRock X370 Killer SLI to a Ryzen 5900X, so i’d like to use my old Ryzen 5800X on my X470D4U.

Unfortunately it doesn’t work very well. I have used the latest beta BIOS, but unfortunately the CPU locks up in Linux.

It seems to be a known issue, i have found a huge amount of people having this issue on this specific board. Unfortunately i didn’t find anyone, trying to fix this issue. So what did i do?

I took the recent 4.21L Beta BIOS and i have updated the microcodes using the UBU Tool. Furhtermore i flashed the modded BIOS using flashrom and an external flasher. Even though, the system still persists, so the microcode update didn’t help with this issue.

Is there anything i may try out?

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