I was given 5 non-working Nintendo Entertainment Systems today at the flea market by a vendor. 3 of them just needed their 72-pin connectors cleaned, but 2 of them won't even flash a red light when I push their power button. The problem is definitely not the power adapter as I used the same one for all 5 of them. When I press the power button the tv acts like "something" (a nearly insignificant audio pop and brief, faint horizontal line flashes) happened but the screen remains black. A little research has uncovered this webpage that states:
"You know that your DC-in board is bad when the game console will not power on. The only way to resolve this problem is to replace the DC-in board."
Does this seem likely/plausible?