Dual Ethernet? Not So Fast...
This is the rear panel of a Gigabyte EP45-DS3R and it has dual Ethernet ports. The Networking pane in System Preferences allows what is called "Link Aggregation". This means that a user of this board can have an Ethernet cable plugged into each of the Ethernet jacks going to a separate port on a modem or router, and it will act as one. This is useful in the event that if there's a physical issue with one of the Ethernet jacks on either the board or the modem/router it is connected to, the other port will take over (at the normal speed of course). Gigabyte claims that you can get double the speed using "Teaming", but you need to have a modem that supports this. Unfortunately it doesn't yield any faster speeds when engaging in multiplayer gaming over the Internet. Don't be fooled!