This HP NX6220 exhibited a number of symptoms but would never show the same one twice in succession. So it was a challenge finding the weak/bad part. As it turns out it was a capacitor under the Wi-Fi card. [Same value as cap to the right]
Replace part and continue checking and checking and turn on. Dead, nothing, no lights, no charge no anything. the choice becomes - Replace or Return to customer since the number of hours are starting to add up with no additional progress.