motherboard with 8 pcie x16 slots - What are Small PCIe x1 Slots Used For? - CGDirector b888 slot

If you have a desktop motherboard with 3 PCIe x16 slots and your graphics card is inserted into the second or the third x16 slot, it will mainly use 8 or 4 lanes, respectively.

PCIe 4.0 expansion cards, such as this $89 ASUS Hyper M.2 x16 PCIe 4.0 x16 card, which is used for high-performance PCIe 4.0 NVMe SSDs, are inserted into PCIe slots, which may or may not be installed on a PCIe 4.0 motherboard.

And users looking for an overclocking-ready Intel gaming motherboard with three PCIe x16 expansion slots might want to check out the ROG Strix Z890-H Gaming WiFi.