I've got a Sapphire Radeon 6870 that seems to have only one working DVI port, of the two on it. Both sets of cables work, one is brand new. Both monitors work. I can't use the HDMI out as I don't have an extension cable. I've tried using just the one that apparently doesn't work after a restart, nothing. I have no clue what's going on. I have the sapphire TRIXX utility to control fan profile, and AMD overdrive to control clock speeds, as well as the basic drivers
for the card.