This product with three output ports, and you can choose one of them to use at a time as you demand, the functions of the port as followings:DVI output, connect the DVI devices using a DVI cable HDMI output, connect the HDMI devices using a HDMI cable. VGA output, connect the VGA devices using a VGA cable. Mini Display Port, connect Mac Book, Mac Book Pro, or Mac Book Air. Note: Only one of the 3 outputs could be used at a time, you cannot use all of them simultaneously.
