Posted 06 June 2011 - 08:12 PM
Laptops are a bit harder to diagnose. A faulty backlight inverter board is possible, faulty backlight lamp is also reported in Google searches.
Once a lamp develops a problem it tends to be fairly consistent, so a symptom that comes and goes is more like an inverter fault. To confirm if the backlight extinguishing is the cause of the black screen, observe the unit in a dark room. If you can see some light bleed from behind the dark screen, it's a video fault setting all the LCD pixels off. If there's no light bleed, you should be able to hold a torch light up against the screen, and faintly see part of the desktop image from torchlight reflected back inside the LCD panel. That's a way to confirm if the video signal is OK, and the backlight isn't on.
Once that's established to be the case, if you feel up to it, you could try getting an inverter board on Ebay and replacing it to see if that's the cause, otherwise I guess you'd need to put the unit in for service.
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