Debug error codes 37-42

Greetings!

I'm having some strange issues with a new build. Some basic Specs:
ASRock 670e Taichi
AMD 7800X3D
G Skill 32G RAM (F5-6000J3238F16GX2-TZ5NR)
Crucial T700 SSD
Asus RoG Strix RTX 2080

PC will boot fine with factory 1.28 BIOS with no mods, but will still throw codes 37, 38, 39, 40, 41, 42.

PC will stall and reboot continually on RAM training (15) if moved to EXPO in BIOS.

Any ideas and/or input is greatly welcome. RAM is on the supported list for EXPO on the 670e Taichi.

Those codes are not in the manual. I believe the cycling is just a CPU temperature readout.

Still having stability issues. Tried another set of DDR5 RAM that isn't on the recommended list and it will post in EXPO mode, but I have frequent random restarts at idle. Without EXPO running everything seems stable even with PBO running and the curve optimizer down to -40. CPU numbers look a bit low on Cinebench23 ranging in the low 16000 stock and 17600 with PBO and -40.

I'm on vacation for a week, but I inspected and reseated the CPU and I'll do a fresh windows install/cmos clear when I get back to rule out software issues.