ASROCK EN2C602-4L/D12 User Manual page 75

For EN2C606-4L / EN2C602-4L / EN2C602:
PCIE2 & PCIE4 Link Width
This allows you to select PCIE2 & PCIE4 Link Width.
PCIE2 & PCIE4 Link Speed
This allows you to select PCIE2 & PCIE4 Link Speed.
PCIE5 Link Speed
This allows you to select PCIE5 Link Speed.
PCIE6 Link Speed
This allows you to select PCIE6 Link Speed.
75