In May, things got messy when we learned that motherboards with the AM4 CPU socket wouldn't support 1st-generation AMD Ryzen (opens in new tab) CPUs, going back on AMD’s promise of full backwards compatibility. It appears, however, that the latest AGESA firmware for motherboards with the AMD X570 chipset (opens in new tab)might just change that.
The point of the new AGESA 18.104.22.168 microcode (opens in new tab) was to bring improvements to Ryzen 3000-series platforms, reportedly cutting boot times by about 20-30% and increasing all-core boost clocks (opens in new tab).
This week, German publication Planet 3D Now (opens in new tab) reportedly got its hands on the 1103 beta BIOS, (which contains the 22.214.171.124b AGESA), for the Asus Crosshair VIII Hero (Wi-Fi) (opens in new tab) motherboard and mated it with a rather unlikely partner: an AMD Ryzen 3 1200. This combination isn’t supposed to work, but apparently it booted up just fine and they even managed to validate the setup in CPU-Z (opens in new tab). The publication noted that they also tried this combination on an older BIOS without success.
What exactly this experiment means for the backwards compatibility across the range of AMD motherboards is uncertain. It's possible that more X570 boards will support first-gen Ryzen CPUs. However, we doubt that backwards compatibility of newer motherboards with older CPUs is what folks are interested in. We suspect more people are interested in having their older motherboards support the latest CPUs (opens in new tab).
Thankfully, some older AM4 motherboards will, indeed, support AMD’s latest CPUs, as Robert Hallock, AMD Senior Technical Marketing Manager, explained in May: "If we look across the ecosystem of motherboards that exist today, we certainly make BIOS updates available to our ecosystem partners to include that on different levels of motherboards in their portfolio, but I don't expect that every motherboard will be updated for 3000-series processors from our partners. That really will be a portfolio decision from their standpoint as well, as to where they apply those updates, and where they choose not to apply those updates."