My amd 6670 is showing gray screen after driver install . When I install windows from scratch then it works with limited resolution but whenever I try to install its drivers via amd website or from windows update . It again shows gray screen . Windows works with iGpu though. And if I uninstall the amd drivers then display from the card works again with limited resolution . So I am not sure if the issue is with card , cpu , pcie slot or power supply. I do not have another card to test.