Quote (Ghot @ 16 Jan 2017 23:17)
Well, you've swapped all the hardware and the drivers and the problem still exists.
The only things left are the motherboard and the Windows install.
/e The only other thing I can think of is to reset the BIOS. I guess if your friend managed to get the very rare BIOS infection, you could try flashing it as well.
I've been thinking reset the bios as I read the thread. Also I agree with you that it might be a bad motherboard or maybe bad PCI slot.
Can you switch that GPU to a different PCI slot and try again? Perhaps your CPU has an iGPU in which case: Can you hook the video up through the motherboard?