Many year's ago I replaced the CRT display with an LCD conversion .And it has worked perfectly for a long time . Lately the screen wont turn on and I have to repeatedly turn it on turn it off and after 5 minutes or so it will light up .No error messages .Machine still has the crt card in the mother board and I would guess it is problem or the board the crt card plugs into . Has anyone had to trouble shoot this type of problem ?