I have just obtained a computer monitor (Packard Bell) but there's no mains lead for me to plug it in. So how is it suppose to work? My friend gave it to me & she reckons she never plugged it into a wall socket, only the computer. It has an 'ANALOGUE-IN' point at the back of it & a 'DC-IN' point, I can see the 'analogue' lead goes into the back of my computer, but there's nowhere for the other lead to go. So it won't switch on. Even if my friend found a mains lead for it, there's nowhere for it to go in the back of the monitor. I don't get it. How does it switch on with no power? Or does it get its power from the computer? If so, how? If I can't rig it up? I'm confused!