Other games are normal. I suspect that a power-related component on the CPS2 B board is faulty, because I used the wrong 12V power supply instead of 5V when I resurrected the B board.
CPS2 19XX has a blue screen at startup and sometimes a purple screen. After a few minutes of power-on, it will work normally after turning it off and on again. Why? Like which capacitor on the board is out of order?