in principle, it is possible to achieve optimum bandwidth over “aggregated” Mellanox CX-2 adapters but I’m not sure you can get as much as 40Gb/s using your old platform but then you’ll need to ensure the following pre-conditions in your system:
1.In case of Windows platform -
to line up with the proper OS, driver & fw that supports CX-2 vpi adapter, which is: Windows 8.1, WinOF driver ver. 4.80 & firmware v2.9.120 (Windows 10 is not supported )
by “teaming” the entire CX-2 adapters on Windows OS (in case teaming is supported in Windows client)
the same goes for Linux- you need to line up here as well with the proper OS, driver & fw that supports CX-2 vpi adapter
Can be found in the release-notes of each OS (see link bellow)
In close, Mellanox CX-2 adapters are already EOF (end-of-life) in terms of sale & Mellanox support. So I suggest you overview the advanced ConnectX-3/4/5 adapters that will provide you the required throughput