I haven't done it myself, but since these are VPI cards, you can put them in Ethernet mode and connect them to a 10GbE switch with the appropriate adapter cable. Performance will reportedly be a tick below the best native 10GbE cards, but for a far lower price, and with the ability to use Infiniband if you need more speed.
Mellanox does make an IB switch with a built-in 10Gb Ethernet bridge, model number 4036E with the "E" standing for Ethernet, but they have not appeared yet on eBay so plan on spending at or near full retail price - $25K retail and probably $14K in real life. In my environment, I just connect the servers to both the Ethernet and the IB networks, with no central routing at all.
Of course if you just need to connect two or three servers, you do not need a switch at all. A simple cable between two nodes works perfectly and, with dual-port cards, you can create a three-node ring.
Can someone help me out with a little more detail please.
It appears they can use a QSFP to SFP+ adapter/cable to get to a 10Gbe switch port.
So if I bought a couple of these and then got a switch or another device with SFP+ ports I could get them working without an IB switch?
Or would it be better to find an IB switch with bridge to 10Gbe?
cheers