AM5 BIOS & Stability Woes

A motherboard’s BIOS is the tiny firmware that starts a PC before Windows loads, and on AMD’s AM5 platform that firmware is suddenly a hardware story of its own: ASUS is moving new 800-series boards to 64MB BIOS chips. (igorslab.de) That change doubles the storage space used for the Unified Extensible Firmware Interface, or UEFI, from the 32MB chips common on many recent boards. ASUS says the extra room is meant for a richer interface and broader support for current and future AM5 processors. (igorslab.de) Firmware space matters because the BIOS now carries more than startup code: memory training, processor microcode, compatibility tables, and sometimes extras like built-in Wi‑Fi support. ASUS documentation for some new boards says future BIOS releases may drop the integrated Wi‑Fi driver if CPU support needs the room. (igorslab.de) (videocardz.com) At the same time, the AM5 firmware stack is back under scrutiny because new user reports say some Ryzen 7 9800X3D chips are still failing on ASRock boards after BIOS 4.10. Igor’s Lab reported the new cases on April 20, 2026, after ASRock had already shipped BIOS 4.10 with AMD’s AGESA ComboAM5 PI 1.3.0.0a code. (igorslab.de) AGESA is AMD’s base firmware package for motherboard makers, the common code they build into each board’s BIOS. ASRock’s own notice for the earlier 4.07 beta said AGESA 1.3.0.0a was meant to “resolve a boot failure occurring on certain CPUs” and improve memory compatibility before that code rolled into stable BIOS 4.10. (asrock.com) (wccftech.com) The immediate problem is that a BIOS update can fix one class of failures without ending the wider debate over board design, firmware complexity, and edge-case stability. GamersNexus, which has tracked the issue since March 2025 and updated its report on April 16, 2025, said the pattern appeared to involve both ASRock BIOS behavior and a possible CPU-side variable, though it said a CPU batch problem did not look likely. (gamersnexus.net) This is also reviving an older AMD motherboard problem: when firmware chips are too small, vendors start trading away features to keep adding processor support. Igor’s Lab tied ASUS’ 64MB move to the AM4 era, when some vendors had to trim UEFI features or support lists as later Ryzen chips arrived. (igorslab.de) Users are getting two different messages at once. How-To Geek argued on April 19, 2026 that BIOS updates now matter for compatibility, performance, and power management, but the site’s separate BIOS guide still says people whose systems are stable and unchanged should follow the vendor’s instructions carefully rather than update casually. (howtogeek.com 1) (howtogeek.com 2) For AM5 buyers, that leaves a simple checklist with awkward implications: check the board maker’s CPU support page, verify the installed BIOS version before swapping processors, and watch whether vendors solve instability with code, more ROM space, or both. (howtogeek.com) (igorslab.de)