Sealed XFX 6950 bought from CircuitCity (TigerDirect) though Amazon. I've tried 10.10e, 10.11, and 10.12, and each of them refuse to install a display driver for my GPU. I thought that the BIOS came to me fucked, so I switched BIOSes using the little switch, and no difference. The instant I pop my 6870 back in, it's automatically installed and works perfectly. Is this card a brick?