I have a gameboy color i purchased recently which seemed to have a come corrosion from battery leakage. I cleaned the board up and truly did not seem bad ( I have seen a LOT worse than this). If you look at the board you really cannot see anything anymore with the naked eye. Anyhow it didnt turn on initially before I cleaned it but after cleaning it extensively it turns on but now shows an inverted screen. Sound works just fine. I did test to see if it was a bad screen by doing a board swap and it is indeed the board but I am challenged to find out where the fault is. Please see attached pics to see what I am referring to. Third pic is when I go to turn it off as the artifact of the screen remains for a few seconds so you can see it more pronounced.