Hi. I don't know if you're asking Bmac or me (the OP) but no, I'm not using iSCSI.
As I already posted, a forum member on ServeTheHome was able to get 2GB/s using a 20Gbps ConnectX IB card from one windows machine to another using plain network shares and a StarWind RAM disk. I'm simply trying to understand why my more advanced 40GbE ConnectX-3 won't give me more than 1.3GB/s in the same environment.
I checked with the guy and he said he tried it both direct connect like I have mine, and through a 40Gbps switch and got the same 2GB/s results.