I have repaired many of these successfully using these steps. For HP/Dell laptops with plain shorts(that short the adapter when plugged in) – I have observed in most cases that the failure was NOT caused by bad mosfets, but by bad capacitors. I have found that adding a light bulb or a fan in series is a good way to observe the path of electricity to get a general idea of where the short is. I prefer a fan because I can hear it spin while keeping my eyes on what I am doing. In some cases, increasing the voltage while using a load of some kind to prevent a complete short has caused more damage to the bad capacitor. The capacitor starts to look like it is cracking. I then remove the bad cap, test it with a DMM – it’s usually shorted.