My Ethernet port on my iMacG4 has failed. Trying to connect my Motorola 5100 surfboard modem to my iMac via anything other than Ethernet. The 5100 has a USB port but needs a driver to make the macOS talk to it. Motorola has no driver available on it's web site.
I'm looking for a converter box of some description that changes Ethertnet to USB and works with mac OS 10.3.9.