compaq nx9420 power supply
i got a 135 watt hp power supply and i using it for this laptop and the original power supply 90 watt but burnt up. But the problem is the laptop has smart battery software for hp popup and tells me wrong power supply plug in original and the switches to the battery and won't go back to the power supply. The battery will charge if the laptop is turn off. Hp uses smart power supply and this is a smart power to tell the laptop that is has enough power. Well thanks for the help.