Thanks all for the help. The issue isn't really solved, but there is nothing that can be done. I have spent over 4 hours with Nvidia Support on live chat, doing everything they suggested and GFE will not open. Tried lots of stuff, nothing works. One good thing, I now have DDU and know hot to use it!
I'll just add something that might be useful.
Generally, leaving both iGPU and dGPU enabled will not cause any problems. This only applies for Intel/AMD and Intel/NVIDIA setup.
For AMD however, it is not possible at all (This only applies for AMD processors with GPUs with them. In short, the APUs and the older AM3,AM2 platforms) as it causes driver conflicts.
If you got an AMD CPU or AMD motherboard that doesn't have iGPU, it should be fine.
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