Precision 3460 SFF ethernet speed way to slow (only ~50 mb/s)

Hi, 

I have a problem regarding my workstation. I'm using a WD MyCloud EX 2 Ultra via ethernet and I only get ~50 mb/s instead of ~100 mb/s, I already know that it is a problem caused by the 3460 or a very specific conflict between the 3460 and the MyCloud, because I tried different PCs with the MyCloud, which got much better speed rates (above 100 mb/s), I even tried to install an ethernet-card, but the slow speed remained. Software-wise there is also nothing I haven't tried to solve the problem, right now I'm also in contact with Dell about it, but there is no solution in sight so far. I more and more tend to think that it's an hardware issue with the motherboard / ethernet-controller.

Is there anyone with this workstation, who could test the speed and tell me their rate? I just want to find out if my workstation's motherboard might have a defect, so I can exchange it for another one.

Thanks!