This laptop has some bizarre issues.
Everytime the thing crashes or I have to just shut it off without going through the normal shut off process (like when a game locks up and won't release the screen back to Windows) the computer won't get past the ROG boot/splashscreen.
I have to take my secondary m.2 out of the slot first, then reboot, then use the computer without it in for a couple of minutes, then shut down the computer and reinstall the secondary SSD and it works again.
It's almost like everytime I don't shutdown properly the BIOS forgets the boot order or something weird. I can't seem to get into the BIOS from this screen either, I always have to get into it from Windows. When both SSDs are installed I get no errors on either of them.
System Specs
Zephyrus G GU502DU
Processor: AMD Ryzen 7 3750H with Ryzen Vega mobile GFX
GFX: Nvidia 1660 Max Q
RAM: 16gb
Windows 10 version 1903 64bit
Storage: 500gb ssd and the secondary one I installed is a Crucial CT1000P1SSD8 P 1 1tb
BIOS version: GU502DU.300 23/12/2019 which I think is the latest model
I have also changed the wifi card to an Intel 9260
I don't honesly know what other details I can give to help.