The RX5700XT series have had lots of problems w.r.t. stability as they are running at GPU "Boost" frequencies that are too high.
However that should not cause a problem when you are installing the GPU Drivers.
Although it is funny when the PC Crashes just after that ridiculous Adrenalin 2020 Installer Explosion Animation scene runs...
I am not so sure about RX5600XT.
Can you take a screenshot of the Main Screen of the BIOS and show me what CPU and RAM frequencies you are running with please?
Here is the download information for the latest version of Wagnardsoft DDU:
Display Driver Uninstaller (DDU) V220.127.116.11 Released. - Wagnardsoft Forum
Please download DDU and please download the latest version of the Adrenalin Driver I pointed you to before.
Can I ask you have you been making sure to completely disconnect from the internet when you run DDU in Windows 10 safe mode and when you then boot into Windows 10 normal mode, you are still making sure that you do not connect to the internet in any way?
Can you please open up Windows Device Manager and send me a screenshot of what Windows shows you about the Display Adapters:
You might want to hide your machine name.