Do I really need -5V for a supergun?

I've been slowly assembling everything I need to build a supergun for the past...decade or so and I have the whole great big pile of junk now.

Now, I have a proper power supply, but I recently came across a really high quality low profile rack mountable ATX computer case with PSU and if possible I'd like to use this. Its really slick and never used. It would make a great housing for a supergun. It has no -5V though, do I need it?

I have a CMVS that someone else built and I'm %90 sure it has no -5V. Right now I have enough of a 'gun than I can power up boards and see them on my monitor (but not control or hear them). I disconnected the -5V and this CPS2 game is running perfectly (as far as I can tell).

So what am I screwing myself out of by putting together a supergun with no -5V? I seem to remember Mortal Kombat needing it, but there is no plan for MK in my life (ever) so that's not a big deal. Do many Japanese JAMMA boards use -5V? For example, I'm thinking about buying a copy of Sky Soldiers soon, will I be able to run it with no -5V?

My plans are mostly MVS, CPS2, and JAMMA shooters. I'll eventually want Atomiswave and maybe Naomi (probably not Naomi).

Like I said, I have a proper arcade PSU, but I'd really like to use the one in this case if possible.

Or maybe I can just do this? http://www.instructables.com/id/How-to-Make-a-Voltage-Inverter/

Whoops, just saw the sticky addressing pretty much this very topic. Sorry!

It kind of looks like I might want the -5V. Maybe I should build that circuit?

Just use an arcade PSU, they're like $20.

As stated, I already have an arcade PSU. This isn't me being cheap, I just really wanted to use this other one. I think I'm going to have to pass on that idea though or its just going to bite me eventually.

SignOfZeta said:

As stated, I already have an arcade PSU. This isn't me being cheap, I just really wanted to use this other one. I think I'm going to have to pass on that idea though or its just going to bite me eventually.

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If the ATX has -12v then you can convert it using a 7904 instead of building that circuit.

Just be careful with your PSU choice. I've had a Neo Geo blow up on me and take a couple games out with it, due to a surge in power. I would never use a cheap PSU again, and doing modifications to an ATX one seems silly if you can just get a proper arcade PSU. I am as stubborn as it gets, sometimes, so I get the, "... but I want to use this one," argument. Believe me, I do. Just be aware that if something goes wrong it could be costly

Unless you're getting really old shmups, we're talking pre jamma, I can't think of many Jamma shmups that need -5v.