How do you know what is AES and what is MVS? I have one of those dual slot arcade machines but have no idea what games go in there. Same ones been in it since I bought it,
The MVS systems were made for the arcade's and they came in 1 slot,2 slot, 4 slot and 6 slots. SNK then released the The neo geo AES (Advance Entertainment System) as home console unit that was marketed towards consumers, to have and arcade experience at home. Your 2 slot machine will only allow mvs carts, the difference between the AES and MVS games is pretty much just the pin out. They did this because back then the AES games were cheaper and they didn't want arcade operators buying AES games and using them in the MVS. This problem can relate to the issue you have with nes and famicom games, same game just different pin outs.
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