Hi,
There could be few things going on here. here is my list ordered with most reasonable at top and go from there:
1) Your HCA is configured to work with Infiniband and not with Eth. you will need to load the MellanoxOFED stack (because the tool we need for flipping this HCA back to Eth is there). then use tool "connectx_port_config" to configure both ports to be in Eth mode
2) use the latest FW available for this card. the one you have (2.8.X) is too old and might give you grief later on.
Mellanox Technologies: Firmware Download
3) recommending on using driver version 1.5.9 or.10 (but get above #1 and 2 done first).
let me know how things go..