Hello, we we have a 50 inch Samsung Plasma TV, from Bestbuy, went to bed and it was working fine, woke up and now we have audio, but NOTHING on screen, completely, black...also tried DVD and same thing, audio and no screen...I hope it's not a goner..

Tries tv unplung,replug it back like about an hour later.For the tv to do a resetting itself back to the factory setting.Tv now 50/50 the tv might work as normal again.If the tv dosen't.Tv have a dead 1 or 2 backlight buffers boards have to be replacing.These 2 long backlight buffers boards only job are to provided a tv plasma screen panel for a backlight to see the picture.Tv now the plasma screen panel have no backlight that why ur tv have only audio sound and no picture.No experience in tv repair and never done any electronic board parts replacement before.Best just call many tv shops and explain the tv situation it in and get the best quote prices for parts and labors.Best prices parts and labors should be around $400 is fair more than that as i said shops around for more tv repair shops.

Sound to me like its the SUB borads they are on the left side of the tv in back remove the cover and look for some burn spot or blow Caps I hope this helps