I think that i have the same issue like you for the Q CODE 55.
Sometimes i shut down the PC, and turn it on, the Q code 55 appear, the screen black. And i force the shut down by pressing the power button, and reboot. The show me this image (image 1) and entre in bios. And i do nothing in bios just reboot. No more issue.
Ps : i have the 0703 version of bios.
This is my spec :
ROG MAXIMUS Z790 HERO
WIN11 PRO 64
BIOS 134882-00158-MB1CI0-A06 0703
ASUS ROG STRIX 4080OC
G SKILL F5-6400J3239G16GX2-TZ5RS