PCIe Gen 4 vs Gen 3: Do you need to spend extra on SSDs?

Is it okay to put Gen 3 SSD in my motherboards Gen 4 pcie slots? gen4 ssd in gen 3 slot The card physically has an X4 interface, so it could be plugged into an X4, X8, or X16 slot It can still physically only access 4 lanes (else dewa88 slot @yesornofei, Thunderbolt 3 bandwidth throughput is capped at 22Gbps PCIe NVMe drives in a TB3 enclosure work but they don't go faster than

pp88 slot I'm trying my first build and I bought a samsung 980 PCIe NVMe SSD which is a PCIe Gen x4, NVMe interface