Unless I'm mistaken, SNK used a cheaper chip set in some models of the Neo Geo for a while when the price for the unit in Japan had dropped by 50% so they could up their sales. I've heard stories that these systems had to have "frequency adjustments" from time to time, but otherwise, they worked just as good as any other Neo Geo.
On a side note, I had to have my Neo cart system adjusted one time. When I got the game Sengoku, I noticed that there were vertical black lines in the picture. I called SNK about it, and the guy told me to send him the system, he'll tune it up for me. Well, I sent the system, he did whatever to it, and since then the picture has been just fine. Occasionally, I can still see the lines in Sengoku, but not as dark or well defined as they were before.
Has anybody else experienced something like this?
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