a data transmission device and a method for the same are proposed . the data transmission device has a first storage device , a second storage device and a transmission control unit controlling the data transfer between a chip set , the first storage device and the second storage device . when the data transfer is performed , the transmission control device checks whether a destination device completely receives the data sent . if positive , the destination device receives the data immediately . otherwise , a portion of the data is first sent to the destination device and a remaining portion is temporarily stored in the second storage device . thus , using the transmission control unit improves the transmission efficiency . furthermore , via storing booting data in the second storage device and using a pci - express interface for data transfer , booting a computer by accessing the data of the second storage device reduces the booting time .