The unit also turns on and off with the computer it is attached to.Įssential Edition My Book drives are almost entirely black, with the exception of a single blue light, used to indicate power and activity, or a circular green light that is located on the front of the drive. In addition to the book-like design, the My Book Essential Edition drives have an Intelligent Power Management feature that stops the drive platters after ten minutes of inactivity, rather than the usual expedient of slowing them down.