Thank you for the post. As you have already tested on 3 different cables and the cables were proven working fine, did you have any problem with the connection?
Where did the I217LM connected to? Is it connected to a switch? If yes, what is the switch model and speed?
I think it might be related with your drivers,did you have update your drivers, you can use Device Manger to update all automatically, or you can download a Dirver Updtaer,such as DriverTuner to scan and update your drivers automatically.