Thanks for the reply.
The card in question is a Hauppauge HVR-1850, confirmed working.
The card has been tried in both the PCIe Gen3 x8 AND x16 slots. The card is not recognized in either of these slots.
The slots are confirmed working.
The card IS recognized and fully functional in both the PCIe Gen2 slots.
If you read my original post, I believe I stipulated that I have already confirmed all of the above but cannot use the Gen2 slots because of the second CPU blocking the first and my video card blocking the second.