AMD's recently released AGESA 1.2.0.5 code for modern AMD Ryzen and Athlon CPUs has been plagued with issues. According to multiple reports, BIOS updates packing the new AGESA code have been prone to serious problems, including CPU performance losses, memory instability, overclocking bugs, and much more.
As a reminder, AGESA code is used to create a BIOS. According to complaints on Reddit, multiple Ryzen users have noted their CPU performance has dropped with the new AGESA code in benchmarks such as Geekbench 5 and Cinebench R20. Some also report higher CPU temperatures and possible WHEA 19 errors when compared to the previous AGESA 1.2.0.3c patch.
But the problems get worse -- according to DeskModder, AGESA 1.2.0.5 is prone to serious PBO and memory bugs as well. High-frequency memory kits such as DDR4 3600MHz are no longer running stably with a rated XMP profile for some users.
The news outlet also confirmed further Reddit reports about reduced CPU performance, with CPU frequency drops of up to 100MHz in single-core and multi-core workloads. Additionally, 5900X and 5950X users have complained about the 2nd CCD "collapsing" with the new AGEA update.
Overclocking capabilities have also been handicapped in 1.2.0.5, with certain voltage values being more limited than before. AMD's PBO menu was also trimmed down with fewer customizations, according to Deskmodder.
DeskModder notes that most of these issues have been a problem since AGESA 1.2.0.4 -- with the exception of the CPU-related performance bugs. Somehow, AGESA 1.2.0.5 inherited all the issues found in the previous version while adding bugs of its own.
Thankfully it appears some motherboard manufacturers are acting proactively. According to ComputerBase, Asus completely halted official BIOS updates to AGESA 1.2.0.5 and will be skipping it in favor of AGESA 1.2.0.6b.
However, most motherboard manufacturers, including Biostar, Gigabyte, and MSI, still have official AGESA 1.2.0.5 BIOS updates available on their respective websites.
If you are an AMD Ryzen owner, we would highly recommend staying away from both AGESA 1.2.0.4 and 1.2.0.5 BIOS updates if at all possible. For now, it appears that 1.2.0.3c is the latest stable AGESA code until AGESA 1.2.0.6b patches arrive which should hopefully fix all these problems.