With broadband access expanding to new areas and being accepted by new customers daily, one question seems to come up frequently. Most cable modems include ports to connect the modem with ether an Ethernet cable or a USB cable. If the cable modem is being connected to a router, switch, hub, or other network device, only the Ethernet cable will work. However, if the cable modem is only being connected to a single computer, either the USB or Ethernet connection can be used, and many users seem to be stumped as to which they should go with.
The main misunderstanding is that users believe one of the connections will provide faster Internet access. While it is true that USB and Ethernet standards have different maximum transmission speeds, you must realize that both standards are much faster than the speed of the cable service being delivered to your house. You’ve probably heard the expression, “the chain is only as string as its weakest link.” That saying holds true for Internet connectivity too. The speed at which you can access the Internet is limited by the slowest link, which is usually the cable service.
However, there are several other things to consider. First, Windows is inherently better at handling network connections through a Ethernet card. When you connect a cable modem to a computer with a USB cable, Windows basically create a virtual network card to handle the connection. This requires more (though only slightly) processing power and memory than using a physical Ethernet card. Furthermore, the cost of a USB cable (which you may have to buy) is usually greater than a similar length of Ethernet cable. Finally, most computers have an Ethernet port integrated, which is useless for anything other than network connections. USB ports on the other hand can support many different devices. It makes sense to save the USB ports for other devices if an Ethernet port is available for use anyhow.
The bottom line: The difference in performance between using a USB or Ethernet connection in this case is negligible. The costs vary depending on the cables you already have and the distance between the cable modem and the computer, but generally using Ethernet is cheaper. All things considered, I would recommend using the Ethernet connection if for no other reason than to save the USB ports for other uses