Cannot get picture from iGPU in Windows with drivers installed

[GamerNerves]

Hi! Early this year I used my PC problem free via the integrated GPU of my Ryzen 7600X, but today, there is a major issue. I just sent my dedicated GPU to warranty service and after some troubleshooting I did with it, I had a dated Adrenaline driver version installed. I plugged my monitor to the iGPU and booted to safe mode to run DDU. Everything went normally, this far I can get, but no matter which driver version I install, after that there will be no picture when reaching Windows. I can uninstall and reinstall drivers by repeatedly booting my PC via the reset button, waiting the amount of time it would likely take before reaching Windows in between, so that a screen comes up eventually about fixing Windows; this way you can get to safe mode.
This is a bizarre issue to me which I do not understand. I have tried two different BIOS versions (mobo MSI B650 Tomahawk Wifi), both working otherwise fine with the dGPU and also have tried to let Windows do it's thing with drivers, but Windows doesn't really do anything. There is a notion about something AMD related in Windows Update, but nothing seems to be actually downloaded nor installed. I can use my PC, as I currently do, with a very low resolution, so without a driver, but of course this is a suboptimal experience. What do you folks here recommend to try out?
Yet one interesting notion is that with DisplayPort it doesn't seem to be possible to get picture out at all, so I'm using HDMI now. Before when everything worked, I used DP as always.

I might add, that if this is somehow Windows related, I can install it again without too much trouble since I am able to save my files from the system drive, so if you think that is the solution, I'll do it.

Thanks in advance for any speculation and suggestions.