hitachi 42edt41

[richman2k7]

ok i have a hitachi 41edt41 and the problem that i had is that it power on but with no picture just sound ok i bought the same tv from a garage sell cheap and it power up with picture showing ok so i did a research on the tv so what i did with the good tv that is working i started with the power supply and swith it so the tv is doing the same thing but with the power supply from the bad tv i put it in on the good tv and it work great so is not the power supply so i went and switch the ysus board and put it on the good tv and still working great so its not the y sus board ok i switch the fomatter board is good so is not the formatter so i switch the upper and lower drive thats not the problem is working great did the same with the z sus board working great so that not the problem so u can say i switch almost everything accept the lower dive so as u can see i switch all the good board to the tv that is bad and all the board from the bad tv to the good tv and is working great but the bad tv is still doing the same thing it power up with sound but with no picture so remember the only thing i didnt change was the lower drive so all i want to know what is the problem anyone thanks