[ofa-general] CX4 Optical Cables

[Roland Dreier]

 > We are just wondering if anyone knows what changed between these two
 > card/chip versions such that the optical connectors work transparently
 > with the the mellanox cards but not at all with the TopSpin/Cisco
 > cards.

optical cables require power from the HCA port (to run the optics,
obviously).  Not all HCAs have power available at the port.  I don't
know of a very good way to tell which do.

The Topspin/Cisco HCAs are basically OEM versions of Mellanox HCAs so
maybe Mellanox can tell you which versions support power.

 - R.