The monitor on my laptop (HP ProBook 6560b) is dying, and the squealing has been getting worse. Now there are two burned-out lamps (LEDs? Fluoroscents?) at the right side; I can sometimes force them on by cycling the power to the screen (using the Fn+F4 hotkey to cycle between monitor settings). When the bad lamps come on again the squealing is louder. I think it may be capacitor plague.