Faulty PCI-e slot?

[InvasionANC]

I'm building a new system with a Foxconn C51XEM2AA and an eVGA 7950 GX2. When I place the card in the secondary PCI-e it works as far as a message coming on the monitor that it needs to be switched to the primary slot. But when I place it in the primary slot it doesn't work at all, though the fans run and it heats up.

What is likely the problem here?