This may be a long shot given the rarity of 4000 series APUs but when installing Radeon Adrenalin 20.8.1 drivers, it will lock up the system instantly and require DDU to not freeze on reboot.
No error is given in event viewer, its just a complete freeze of the system that requires holding down the power button. The OS is Windows 10 build 2004.
System:
Motherboard: Asrock Deskmini A300
BIOS Version: 3.60R
RAM: 2x16GB 3200C18
CPU: Ryzen 7 4750G
I've tried all sorts of obscure solutions from other people including disabling the sata controller, device manager installation, trying bios version 3.60N and 3.60O, and reinstalling Windows. XMP is disabled, so it is on its jedec 3200c22 profile.
I can only hope its not an issue with the physical iGPU...