I have a Acer Aspire 5520 laptop I'm trying to fix and can't find out what is wrong with it. When you press the power button it lights up green for about 2 seconds then turns off while making a clicking sound. It then tries to come on again on its own doing the same thing over and over. Nothing comes up on the monitor. I already know its not the battery because I have taken the battery out and hooked it up to an electrical outlet and it does the same thing. I'm not sure if this makes any difference or not, but I tried taking the hard drive out completely and turning it on just to see what it would do. It did the exact same thing, just minus the clicking sound.