Hello,
Did you enable DOCP prior to the issue occurring?
1. Turn off the computer and unplug the power cord
2. Locate CLRTC pins as per snip below
3. Short circuit the pins with a jumper cap or carefully with screw driver tip for 5-10 seconds.
4. Plug power back in and attempt to boot.
13900KS / 8000 CAS36 / ROG APEX Z790 / ROG TUF RTX 4090