Different pinouts on each PCIe connector at the device end

For the PCIe interface via the card PCIe Edge connector For System NIC mode, it's direction will turn as input Mechanical Key 12 GND Ground

The PCIe card slot connector is often used on system motherboards to enable PCIe expansion cards to be added, such as graphics or network adapter cards DSTREAM

pcie 1 slot Slot 1

pcie slot configuration gen1 gen2 gen3 ConnectX-6 single-slot Socket Direct cards offer improved performance to dual-socket servers by enabling direct access from each CPU in a dual-