I have a Dell Inspiron 5100 and the AC power cable split in half and no longer works. I used both batteries up to the utmost fullest (I know, I'm retarded), so they no longer work either. I borrowed a friends AC power adaptor from a slightly older Dell, the wattage was about the same, but the laptop still doesn't turn on. The front 3 lights will turn on for a second, the fan will turn on, but everything will shut off after about 1 second. If I insert the power cable in and out really fast so that the front lights come on rapidly, the laptop gets enough power to turn on by itself (without me hitting the power button), but then dies back down. I then bought a Targus Universal AC adaptor but it does the same thing as the other Dell cable. I'm out of my warranty and hardly any computer place will touch a Dell, so I'm turning to OT for some advice. Should I buy the actual power cable for my notebook? Purchase a new battery? Bring it to somewhere and have them diagnose it for a hundred bucks? Help me out!