I've noticed there's at least 3 variants on the 4 slot boards and one of them has a 2 pin JP1 socket on the top board.
Looks to be for additional power or connection to the bottom board and if so where is that connection taken from as the bottom board has no connector in the JP1 position.
See link, its in top right next to big blue cap/battery
https://wiki.neogeodev.org/index.php/File:Mvs_slot4.jpg
Looks to be for additional power or connection to the bottom board and if so where is that connection taken from as the bottom board has no connector in the JP1 position.
See link, its in top right next to big blue cap/battery
https://wiki.neogeodev.org/index.php/File:Mvs_slot4.jpg