I don't think this is a motherboard issue but it's possible. Check to see if the card is recognized in the device manager and in the AMD Catalyst software. If it's there then I don't think it's an issue with your motherboard. You may need to tweak Catalyst settings to enable the second card to output. I have never had 2 AMD cards but if you have Crossfire enabled you may need to disable it.
A bus station is where a bus stops. A train station is where a train stops. On my desk, I have a work station…