Reports have appeared where there is a significant issue on the six-core/12-thread (6c/12t) Ryzen 5 7600X, where the AGESA update is seemingly disabling some cores. Users can experience significant performance loss, and systems may fail to boot.
It is noteworthy that not all Ryzen 7600X CPUs may be affected. The bug is only present on those 7600X chips with their cores across two CCDs (core chiplet dies) as the AGESA update disables one of the core chiplets.
It is believed that the System Management Unit (SMU) version 84.79.204 is buggy, and a new SMU 84.79.210 should fix the issue.
It is not clear if other dual-CCD Ryzen chips are affected. If it does, it will include the Ryzen 9 7950X, 7900X, and at least some Ryzen 7700X units.
Currently, the cure is to roll back to the previous firmware release and download the BIOS from their corresponding motherboard’s “support” section. Motherboard makers have also started pulling the AGESA 220.127.116.11 update from their websites.,