Solution
The PCIe‑8398 is a full‑length x16 PCI Express card, and it can operate in any PCIe slot that physically accepts an x16 connector. This includes x16‑sized slots that are only wired for fewer lanes, as well as open‑ended slots that allow full‑length cards to be inserted
PCI Express automatically trains the link to the highest number of lanes supported by both the device and the slot, so the PCIe‑8398 will operate normally even if the slot provides fewer lanes.
Using fewer PCIe lanes reduces bandwidth proportionally, so an x8 slot cuts the PCIe‑8398’s throughput to half of x16 operation.
Some motherboards may negotiate an even lower link width, so an electrically x16 slot is recommended for maximum MXI performance.