We do LCD repairs here in our shop. To know what ones need to be replaced by looking on the tops they will be domed not flat. The ones that have small cuts in. Look at the little cuts are they deep or shallow? if they are not the same as the others around it then they are no longer good. And you dont have to remove the solder on them just WARM it up (not burn) so that it will brake lose then do the other side (leaving the solder on the board) then when you go to put the new one on you can rewarm the solder. Make sure you put the + on the + and the - on the - it DOSE matter on how its installed.
The other things that can make a lcd screen not work is the led light. So once you did the first repair an it still dose not work, then you need to find out where the led lights are on that screen take them off an replace. Again another very cheap fix.
Desktop, laptop an tv LCD screens are pretty much all the same. But the tv screens have more things on there because a computer screens only shows one item (the desktop) where the tv screen is set up for more than one tv show/video games an so on but all in all its the same deal.
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