Use Riser 2 P/N CY3R8. Note that processors 1 &2 must be installed to use the x16 and x8 data  link on the riser 2 slot
Hi, I've a R630 ( Chassis with up to 8, 2.5" Hard Drives, up to 2 PCIe Slots ) and I need to add a HBA controller to it (405-AAES, low profile). I figured out that I need a riser, but which type? Is there a specific part number ?  Thank you, Patrih
R630 optional riser