OK, test complete, I can conclude that
a) My first card has a defect and cannot be detected in the x16 slot.
b) There is a conflict between the Asrock x1 slot and my onboard Atheros nic and a PCI Dynex nic. I cannot create a network bridge with the x1 slot.
The only config I can get to work is the replacement infinitv4 card in the x16 slot with a PCI dynex nic.
I moved the infinitv4 card back to the x1 slot and had a flashing blue light. I reset the network settings and...