I have a GPU that I know to be working, and I'm fitting it my second computer.
Sometimes it works, sometimes it doesnt. When it doesnt, my display is dark from the start. Like the BIOS / mobo doesnt realize a GPU exists.
I'm trying to install Windows but during the reboots, I lose the GPU and the installation gets fucked (no integrated GPU on mobo)

What's causeing this? I know the GPU works with the other mobo. The mobo should also be gud because another GPU works on it.