you have two types of pcie lanes, those that come directly from cpu and those that come from chipset, so the 10th gen intel X series cpu’s have 48 lanes which are directly wired to pcie slots so are extremly fast and each motherboard manufacturer decides on how to wire them to cpu, my msi creator x299 motherboard has 4 full sized (x16) pcie slots that run @ x16/0/x16/x8 0r x8/x8/x16/x8 (these are all directly wired to cpu) and these bifurcation (meaning seperating the lanes as needed is done by bios) varies by the type of cpu installed, so when someone says pcie lanes they mostly mean pcie lanes directly connected to cpu, then there is the x299 chipset and it is connected to peripherals like ethernet port, usb ports, sata ports and then it is connected to cpu with x4 pcie lanes, with non hedt cpu’s they only have 16 lanes coming from cpu that connect to pcie slots but during boot the bios determines if a slot should run at x8 or x16 speed based on what else is installed in the pcie slots that are directly...