What is the difference?

Vision Tech makes the Killer nic in a stand alone nic card called the Vision Tech Killer Nic 2100 . When the Killer Nic is embebed on the motherboard or in this case a combo card they use just the chip and its called a E-2100 , there is no difference between the two and all the features and capabilities are the same. If you go to the Vision Tech site you can find out all the info you need.