What are the top uses of PCIe x1 Slots?

In ASUS 「PCIe x16 Slots - 7」

On PCIe X1, X4 and X16 slots, the first 18 pins are all wired the same, so as long as the PCI-Express card fits in the PCI-Express slot, it

pcie 50 slot The biggest and best PCI Express slot is the PCI Express x16 slot Pretty much the only thing that uses x16 slots outside of graphics cards is server-grade

pcie slot bracket PCIe x16 Gen expansion backplane with two slots The PCIe x16 Gen3 backplane has two PCI Express x16 slots, with one slot supporting the OSS target