PE-5S 5-slot backplane with one PCIe x16 slot, one PCIe x4 slot and two PCI slots RACK-500G 5U 5-slot full-size
HPXE2-5S1 5-slot PICMG 1.3 backplane for half-size SBC, with two PCI slots and one PCIe x16 slot (x16 signal)