I downloaded AMI BIOS 7C56vAC1(Beta version) dated 2023-03-03 and flashed it to my B550-A Pro motherboard. I immediately got a WMR error mesage that my G2 headset wasn’t connecting.
I haven’t had the chance to troubleshoot it yet (I will tomorrow.)
Am I dumb to even try running a Beta BIOS? The reason I did was because I’m about to install a 5800X3D and wanted the latest BIOS. I was already on the latest non-Beta BIOS (7C56vAB
dated 2022-08-15.)
Slightly different I’m on a B550 Mortar and have the MS-7C94 bios released 22/08/17 following on from a previous beta which had less memory support but slightly faster stock timings - otherwise there was no difference that I could see.
There again the X3D never existed then.
New isn’t always better. Changing to a new let alone Beta BIOS is risky business unless you know what you’re doing. Any kind of core OS software/hardware components I would stay away from pre public stable releases.
Uefi bios seem to be a pretty safe nowadays, I haven’t heard much bad about betas for a long time (or at least not those offered by MB manufacturers). Sure you could be really unlucky and have them brick your PC otherwise 99.9% of the time its pretty easy to roll them back if they give any problems. Just remember to back up keys for your bitcoin wallet etc. or it could be expensive.
Edit: I took the chance on the beta and here I am back … of course now I’ll have to review all my bios settings and redo my overclocks … who says PC’s aren’t a bunch of fun? 
Edit: Edit: … Nothing new in it for me so probably it’s just PBO support for the 5800X3D
OK … my findings (with my 5800X)
Cinebench a tad slower, not enough to worry about (3 runs)
Initial boot times quite a lot slower (pretty normal for a beta)
ResizableBar enabled by default but 4G support disabled by default … so check afterwards and enable/disable as required
Conclusion: Only upgrade to these bios if you have a 5800X3D.
Thanks. I did notice that RBAR was enabled by default, but didn’t check ‘Above 4G’.
I have 64GB and an RTX 3090 Ti, so it should definitely be turned on.
I’m going to swap in my new 5800X3D later today.