pci express - PCIe x8 NIC in PCIe x16 slot - Server Fault

Yes, you can plug in in and it will work fine. Long version: Three things are important for PCIe connection: PCIe version (v1, v2 or v3. Lowest common version is used) Number of lanes on the card you plug into a connector (e.g. x1, x4, x8 or x16) Number o

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