Actually with the right NIC's and drivers you can do NIC teaming, as the name suggests the NIC's team up your PC sees it as one connection but its actually 2 or more physical, Although I know that most computers don't have this function, he said the card came from a server, So it may, with the right drivers, have this function. Im not trying to say your wrong. Im just trying to give you more knowledge, Obviously you are correct about the cable from the computer to the router not being a bottle neck