Sb6120 and Gigabit with RB751-2HnD-IN

Hello to Everyone ,

I have a problem , i got a Sb6120 Modem Cable , and a Rb7512hnd , the problem is , when i plug the Ethernet cable directly to the Computer , the ‘‘led link status’’ of the modem is Blue ( that indicate the gigabit port connection between the two adapter ) , but when i plug the Ethernet cable on the Routerboard ‘‘Eth1 Interface’’ , the ‘‘led link status’’ is ‘‘orange’’ ( that indicate a non-Gigabit port ) . The problem is , when i took the routerboard , the vendor said it will work as gigabit port . I have tried to force the gigabit link through the Eth1 interface ( picture attached ) but it don’t work




i don’t know how to make it work

RB751u does not have gigabit ports.