AGESA v2 1.2.0.5 FIrmware for AMD Ryzen Can Cause Performance Problems

If you're have planned a firmware BIOS update towards the latest AGESA v2 1.2.0.5 FIrmware, then you might want to install an older version or just wait a little. Especially tweaked systems in particular are suffering according to reports on Reddit

Numerous end-users have reported issues with the current firmware for the AM4 platform, which is now being distributed as the final version by numerous mainboard makers. The manufacturer has regularly added additional functionalities to its in-house program library for processors and chipsets, AMD Generic Encapsulated Software Architecture (AGESA), for BIOS and UEFI developers of its board partners up to version v2 1.2.0.3c, but these now vanish.

According to multiple forum posts, the author's personal testing with an AMD Ryzen 9 5950X (test) on an MSI MEG X570 Unify, and several Reddit conversations, installing AGESA ComboAM4v2 1.2.0.5 may result in the following issues as reported on computerbase:

• "Drops" of up to 100 MHz with the single core clock
• "Drops" of up to 150 MHz with the multi-core clock
• Missing overclocking functions eg with PBO
• A significantly cropped CBS/PBO menu
• Performance issues with the second CCX
• Low fabric clock (FCLK) possible
• More WHEA-19 errors after OC

After initially attributing a significant amount of the faults to the firmware's beta condition, certain board partners have recently published AGESA ComboAM4v2 1.2.0.5 as the final version for their motherboards. A "downgrade" from AGESA v2 1.2.0.5 to 1.2.0.3c is also not possible, depending on the manufacturer and mainboard, which is why the latest firmware should only be installed by experienced users and with extreme caution. 

MSI has already reverted to BIOS 7C35vAC1 after briefly deploying AGESA v2 1.2.0.5 as the final BIOS. Other manufacturers, such as Biostar and Gigabyte, have already published final BIOS updates based on AGESA v2 1.2.0.5, however they occasionally run into the same problems. Additionally, far lower voltages and clock frequencies have been reported. Asus, on the other hand, is adopting an entirely different strategy. After releasing multiple beta versions with AGESA v2 1.2.0.5, the manufacturer chose to go straight to AGESA ComboAM4v2 1.2.0.6b and not issue final versions of their BIOS with AGESA v2 1.2.0.5 at all. Only Biostar, Gigabyte, and MSI now provide final versions of AGESA v2 1.2.0.5, while ASRock distributes beta versions and Asus continues to actively develop AGESA v2. 1.2.0.6b. Gigabyte is already working on version 1.2.0.6.