Jamma Power Question

I'm under the impression that the -5 is only used for peripheral items like lights and coin counters. Does anyone know of games that require -5 for the logic, to operate?

For logic +5v is enough. On some boards however -5v is necessary for sound (not coin counters, at least within the jamma standard as those work with +12v). Search for old threads to find which games use it (early 90's Williams/Midway boards for instance).

The Mortal Kombat games, Killer Instinct1/2, newer Midway/Atari 3d games like Blitz, CarnEvil, Gauntlet Legends, and I believe alot of the early-mid 90's Konami games need -5 also.

Some of these only need -5 for sound, however some of them(KI in particular) won't boot if the sound system isn't running.

Ok, the sound makes sense. My ultimate question is do you think I'm screwed if I only give -5 300mA in a super gun. The game's I'm playing right now don't even use -5, but I decided to implement it for completeness' sake. I need to use an external PSU for size reasons, so I'm limited to what jameco has to offer, and I think I need to end up regulating -15 or -12 down to -5 already. What would you recommend as the minimum current source for -5?
Thanks much.

Well, the current on -5v must be very little on all the boards that need it, as arcade PSU's designed for Jamma games are usually rated no more than 1A. Whether 0.3A is enough I don't know...

If you are building a supergun, you best bet is just to buy a $20 arcade power supply. Should run any board(including 6 slot MVS), doesn't look much worse than a desktop PSU, and is fairly small(maybe 7" long, 5" tall, 2" deep). I use one in my supergun.