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I have a Samsung LN32D40. I turn on the tv, the tv makes the "turning on jingle" as normal, then the speakers make a high pitch noise, and then the tv appears to turn off. I cannot tell if the tv stays on, and there is no picture, or if it shuts off. How can I tell the difference?? When I...

I just purchased a used HP ProBook 4440s. It was purchased with the previous owner not knowing what was wrong. I turned it on, and the screen lights up, but it's all black and doesn't display anything. I can tell when the screen is black due to no power to the laptop and when the monitor itself...