Recent reports of new Ryzen 5000 processors running on ASRock's A320 motherboard has generated plenty of excitement. Now, a new BIOS posted at jzeletronic.de enables support for AMD's Ryzen 5000 and Renoir processors on ASRock's X370 Taichi and Professional motherboards (via @komachi_ensaka). For those not in the know, AMD has expressly stated that support for Ryzen 5000 processors will not come to 300-series motherboards, making this an interesting development. We pinged AMD on the matter, and the company issued the following statement to Tom's Hardware:
"AMD has no plans to enable or support AMD Ryzen 5000 series on AMD 300 series chipsets."
Regardless, it appears this is the first publicly-available BIOS that enables Zen 3 support on an X370 motherboard (with serious caveats we'll outline below). AMD only officially supports the Ryzen 5000 models on 500-series motherboards for now, but the company is currently working to bring complete compatibility with 400-series motherboards in January 2021.
You can download the new P6.61 BIOS at the website, but you should absolutely proceed with caution - the BIOS is an alpha revision, and it's unclear if ASRock itself has provided the BIOS. As an alpha version of the BIOS, it is in the earliest stages of development. That means there is a distinct possibility of serious bugs, and flashing your BIOS can be a risky proposition, even under the best of circumstances. We wouldn't advise you to be the beta tester of an alpha BIOS, but if you must, know that you proceed at your own risk.
The BIOS revision may simply be a modded version of an existing firmware, made by an enthusiast or otherwise. The new BIOS revision comes on the heels of numerous reports that users have simply flashed the X470 Taichi's BIOS to older X370 Taichi motherboards and successfully enabled support for the Ryzen 5000 processors.
For instance, resourceful enthusiasts have been known for modding BIOSes to enable previously-locked features. Adding compatibility for unsupported processors comes with quite a bit of risk, though. There's a big difference between a processor technically working (i.e., booting up) and a processor that actually works as intended. While the processors may work, they might encounter issues with some memory configurations or not support all of the processor's normal features.
It's unclear if we will ever see support for Ryzen 5000 series processors come to official ASRock X370 BIOSes, but it wouldn't be without precedent. In the past, motherboard vendors have enabled features they simply weren't allowed to - like the nearly industry-wide decision to enable overclocking for AMD's locked Athlon processors, which wasn't officially condoned by AMD. Later BIOS revisions from the motherboard makers locked out the unsanctioned Athlon overclocking feature, but it was fun while it lasted.
We've reached out to both ASRock and AMD for comment and will update if we learn more.