Check what changes in lspci
command between not having the GPU connected vs. Having it connected.
I am suspecting that your PCI-E bandwidth is getting exhausted once the kernel activates your GPU.
Edit: Although I could be wrong about this. So makes sense to try passing “nomodeset” to your kernel parameters and see if that changes anything.
So it’s morally fine for assholes to pay money and buy up rights to creative works and deprive people of enjoyment just because their imaginary concept of ownership trumps ours?