Summary
Examine the motherboard for physical signs of damage when the processor shows fewer PCIe lanes.
Description
The maximum number of PCI Express lanes in the Intel™ processor i7-8700K is 16. However, my processor only shows PCIe x8.
Resolution
Inspect the motherboard to make sure it is free of physical defects, especially the PCIe connector pins. If there are dents/broken pins, please contact your motherboard manufacturer.