How is the 19 inch PCIe Gen3 I/O Expansion Drawer connected on POWER8 systems?

A.
PCIe Gen3 InfiniBand Adapter

B.
GX++ Bus

C.
Optical CXP Converter Adapter

D.
PCIe x8 SR-IOV Adapter

Explanation:
PCIe3 x16 adapter provides two optical CXP ports for the attachment of two active optical cables (AOC). One
adapter supports the attachment of one PCIe3 module in a PCIe Gen3 I/O Expansion Drawer.
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ENUS9119-_h05/index.html