Hey! I upload the new bios.
ROG MAXIMUS XIII HERO 0706 BIOS
https://drive.google.com/file/d/1K_ALdvRjhLCP3Iz0W8fXmODIiWN3MHSN/view?usp=sharing
ROG MAXIMUS XIII APEX 0706 BIOS
https://drive.google.com/file/d/1C5Bt7CmfgLPt7u3HbyN5MV-nzmIQv5yV/view?usp=sharing
ROG MAXIMUS XIII EXTREME 0706 BIOS
https://drive.google.com/file/d/1W1UAVWfvZ3X4c7UClqrApl0RHf-R-pPN/view?usp=sharing
ROG MAXIMUS XIII EXTREME GLACIAL 0706 BIOS
https://drive.google.com/file/d/14Vtapv3ipzYrgSeuD2-FEaG5M-pdjZZR/view?usp=sharing
From shamino
Some refinements to gear 1 , in particular cmd rate 1t mode , plc check if helps!!
I use 1.45v io mem and 1.6v SA for 3866 1t just to rule out voltages
ROG-MAXIMUS-XIII-APEX-ASUS-0062.rar
ROG-MAXIMUS-XIII-EXTREME-ASUS-0062.rar
For SUPERPI (APEX 0062 MOD BIOS)
https://drive.google.com/file/d/1X9FdwK1MX5YkoBTYJsSqTgjiR5NEdqXD/view?usp=sharing