PCIE 1x, 4x, 8x, 16x bus pins and signals

What is the difference between PCIe Gen 3 and PCIe Gen 4? pcie slot configuration gen1 gen2 gen3 To summarize the discussion: The UEFI settings under PCIE1 Link Speeds are Gen1, Gen2, and Gen3 PCIe mobo slot? Andor any chance pcie x 16 slot PCI Express Gen2 and Gen3, IO Virtualization, FCoE, SSD and PCI Express Storage Devices are here What are PCI Express Storage Devices

pcie 8x slot Question For X9DRX+-F, in the BIOS setup under North Bridge -> CPU 1 slot for PCI-E, the options are Gen1, Gen2, and Gen 3