An apparatus comprising: a circuit board; a device located on the circuit board; a first Peripheral Component Interconnect Express (PCIe) connector located on the circuit board and coupled to the device, the first PCIe connector arranged to couple to a first connector of an additional circuit board; and a second PCIe connector located on the circuit board and coupled to the device, the second PCIe connector arranged to couple to a second connector of the additional circuit board; wherein: each of the first and second PCIe connectors includes conductors, the conductors of first PCIe connector include a first group of conductors on a first side of the circuit board, and a second group of conductors on a second side of the circuit board; the conductors of the second PCIe connector include a first group of conductors on the second side of the circuit board, and a second group of conductors on the first side of the circuit board; and the first group of conductors (111A, 112A) of each of the first and second PCIe connectors is arranged based on PCIe connector pin-out specification for a first side of a printed-circuit-board, and the second group of conductors (111B, 112B) of each of the first and second PCIe connectors is arranged based on PCIe connector pin-out specification for a second side of the PCB, such that the PCIe connector pin-out specification for the second side of the PCB is opposite to the PCIe connector pin-out specification for the first side of the PCB. a circuit board; a device located on the circuit board; a first Peripheral Component Interconnect Express (PCIe) connector located on the circuit board and coupled to the device, the first PCIe connector arranged to couple to a first connector of an additional circuit board; and a second PCIe connector located on the circuit board and coupled to the device, the second PCIe connector arranged to couple to a second connector of the additional circuit board; wherein: each of the first and second PCIe connectors includes conductors, the conductors of first PCIe connector include a first group of conductors on a first side of the circuit board, and a second group of conductors on a second side of the circuit board; the conductors of the second PCIe connector include a first group of conductors on the second side of the circuit board, and a second group of conductors on the first side of the circuit board; and the first group of conductors (111A, 112A) of each of the first and second PCIe connectors is arranged based on PCIe connector pin-out specification for a first side of a printed-circuit-board, and the second group of conductors (111B, 112B) of each of the first and second PCIe connectors is arranged based on PCIe connector pin-out specification for a second side of the PCB, such that the PCIe connector pin-out specification for the second side of the PCB is opposite to the PCIe connector pin-out specification for the first side of the PCB. each of the first and second PCIe connectors includes conductors, the conductors of first PCIe connector include a first group of conductors on a first side of the circuit board, and a second group of conductors on a second side of the circuit board; the conductors of the second PCIe connector include a first group of conductors on the second side of the circuit board, and a second group of conductors on the first side of the circuit board; and the first group of conductors (111A, 112A) of each of the first and second PCIe connectors is arranged based on PCIe connector pin-out specification for a first side of a printed-circuit-board, and the second group of conductors (111B, 112B) of each of the first and second PCIe connectors is arranged based on PCIe connector pin-out specification for a second side of the PCB, such that the PCIe connector pin-out specification for the second side of the PCB is opposite to the PCIe connector pin-out specification for the first side of the PCB.