This is a quite common issue I've seen reported many times online, and experienced myself with my SCAR 18 (2023): sometimes randomly (still uncertain how to reproduce it) you'll find the USB-C/Thunderbolt/DisplayPort port not working anymore and in Device Manager the yellow triangle for example for: UCM-UCSI ACPI (Error 43 ) + Intel(R) PC Express Root Port #25 - 7A48 + Intel(R) PC Express Root Port #9 - 7A30 (or similar).
It won't go easily away with a simple Shutdown or after you disable/re-enable/uninstall these devices from Device Manager:
THE FIX
Don't worry, you don't need to RMA the laptop, just follow this procedure to get rid of those device errors and restore USB-C multi-port:
- shutdown Windows 11, and disconnect power cord ( = DC battery mode only)
- keep pressed power button for 40secs (keyboard leds will light up, ignore this and keep the button pressed)
- laptop will totally turn off in the process
- wait 60 secs more doing nothing, then press the power button to wake it up...
- ... at this point the keyboard LEDs may light up, but the screen remains black and it might auto-reboot twice; don't worry, just wait and it will turn itself off
- then press again power button and the PC should finally boot up as usual... problem gone!
NOTE: your BIOS undervolting will survive this BIOS reset.
Enjoy your powerful laptop!
P.S.
ASUS should definitely investigate this common issue on their recent laptops anyway...
