and yet, here you are with no closer explanation for your problem. this path you've chosen is working out quite well for you.
the reason for asking for diagnostics is to give the ability for others on this forum to provide you with as specific a resolution as possible on the first attempt, and not after 47 guesses wasting your time and ours.
But if you'd like a guess about the problem based on what you gave us, here are a few: bad gpu, bad wiring, mouse in the computer eating your wires, misconfigured syslinux.cfg, hardware error, lack of iommu support, lack of virt support, monitor power cable not plugged in, one-D-ten-T user, gpu not seated properly, monitor display cable not plugged in, hdmi cable plugged in wrong port on gpu, bad cable from server to monitor, ghost in the machine, bad install on multiple vms, misconfiguration of drivers for windows, gpu too old, motherboard too old, cpu too old, misconfigured ovmf, or other user error yet to be determined at this time due to lack of proper diagnostic files.
start with those.