For the nvidia card to output something from the virtual machine I had to, of course install the proper drivers but before that I had to enable secure boot, or at least UEFI, even though I wasn’t able to get pure UEFI to work. And also switch video from QXL to None.

UEFI x86_64: /usr/share/OVMF/OVMF_CODE_4M.secboot.fd