Never heard of this before. The Crack sound and a Freeze situation. When it fails to boot what exactly does it do or not? Have you tried on ext. monitor when it fails to boot? I'd start here.. If its the Screen backlight its possible the sound you heard was approximatley 1.6KV ac snapping to ground. This could definitley cause a freeze state due to the discharge. You may have a slightly chaffed or loose inverter cable, and this coupled with high humidity might have arc'd the voltage outside of the CCFL.. (I'm just guessing at this point).. We'd love to diagnose this one for you if you'd like.. Good luck!
Ken
www.ikenfixit.com
here is the issue in a nutshell:
Have a HP Pav zt3000, 13 months old.
Was on vacation. Last day was rifling through my digital pics with gramps when I hear a sharp "crack". After cleaning urine soaked carpet, I realize that the screen is locked up, still showing the last picture we looked at. Nothing working at this point, lights still on, but buttons seem to be inactive. I turn off computer by holding down power button for a few seconds. Restart the computer, lights come on...but no screen, and the buttons still unresponsive. Fast forward to today..I recovered my pictures, but only after attempting to restart my laptop 20-30times. In other words, my HP only actually started correctly once in those attempts. And it only ran for a few minutes, but functioned correctly during this time period. Can anyone help me?

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