[lukevanoort]

I don't think this has been specifically mentioned; make sure you have a switch/router, not a hub. The difference is a touch technical, but computers communicating through a hub is like trying to get a message across a room when everybody (including you) is communicating in Morse code--with airhorns. Communicating through a switch is like having everybody make quiet phonecalls to one another. Naturally, this makes a huge difference in the game's performance.