What are the top uses of PCIe x1 Slots?

The link given by ko888 shows some of the mini PCI-E cards that go into that slot Those include: Ethernet card, LAN card, RAID controller,

Mini PCIe slots are generally found in older desktop PCs and laptops, but can also see some uses in spaces outside of consumer electronics, like

minipcie slot Mini PCIe slots are generally found in older desktop PCs and laptops, but can also see some uses in spaces outside of consumer electronics, like

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