Intel PRO/1000 PF Quad Port Server Adapter & Intel PRO/1000 PT Quad Port Server Adapter are not detected by the system when inserted into a PCIe 2.0 slot. If you require a Quad Port server adapter & have PCIe 2.0 slots, Intel recommends you use any of the following: Intel Gigabit ET2 Quad Port Server Adapter (P/N E1G44ET2)