I was running a EVGA 760 up until a few hours ago which I replaced with a 970. When I have the power supply attached to the new card, the onboard graphics won't work, and neither will the card. When I disconnect the card, the onboard graphics works, but the system won't detect the graphics card after I reattach the power supply to it, and therefore it won't allow me to install drivers.
EVGA thought it might be a compatibility issue with the bios (or the board), as it's might simply be too old to run the new card. Anyone have any ideas?