scaryone I'll have to update the picture when I get a chance. I don't have a moment right now. The board itself looks like just a PCI slot for the riser board in either case. It won't give you the PCIeX16 speeds since you are having to go through an additional pathway to get at the CPU itself. Since the CPU and PCIe slots work in conjunction with each other to attain the speeds I really have serious doubts you can even get close to PCIe_x16 speeds using an additional riser.
KenMcC If what is say is true, and I have no reason doubt you, the Slot is not a PCIe x16. It cannot be called such unless it is fully compliant with the PCIe specifications. That mean an x1, x4, x8, or x16 can be plugged into it and fully function. All Poooo to HP, they lie.
scaryone Have you taken a look to see if it conforms to the PCI-X slot designs? It is possible they are using that for the connections. I did happen to update the picture and changed the location of the image.