I've seen some small external desktop style power supplies that people have used for custom built jamma systems... does anyone know where I can look for these?
I'm not sure if they offer 5v adjustment.. maybe I should stick to a regular psu?
small, desktop power supplies suitable for jamma?
NO NO NO NO NO NO NO.
Get yourself a proper power supply. Most modern boards dont need -5, some games do, many older ones. Whatever you get, you need an adjustable 5v. If your 5v is set correctly and doesn't over or undersupply your boards, they will work more reliably and last longer. As an example, hit a Nemesis with 6v and you can pretty much kiss it goodbye.
Adjustable 5v is incredibly important. Plug a Cave PCB in, adjust to around 5.05 to 5.06v under load (running), now plug a big older 2 layer game in. You'll find the draw is different and it might be running under power. Reverse that logic, adjust a big 2 layer boot to 5.06, now plug a modern board in, odds are you'll be hitting it with 5.4 or so, and that's not good.
Please don't take the advice of anyone who claims PC supplies work fine for them - maybe they do, maybe they don't - you're stuck with whatever setting it has however, and the price differential between a good quality 2nd hand (or new!) arcade PSU and a PC PSU is less than the cost of a PS2 game, and certainly less than the cost of a PC.
I've restored many arcade machines, and had a collection of PCBs second only to the madness of Shou-sama, one thing I learned is not to take chances with power supplies..
Get yourself a proper power supply. Most modern boards dont need -5, some games do, many older ones. Whatever you get, you need an adjustable 5v. If your 5v is set correctly and doesn't over or undersupply your boards, they will work more reliably and last longer. As an example, hit a Nemesis with 6v and you can pretty much kiss it goodbye.
Adjustable 5v is incredibly important. Plug a Cave PCB in, adjust to around 5.05 to 5.06v under load (running), now plug a big older 2 layer game in. You'll find the draw is different and it might be running under power. Reverse that logic, adjust a big 2 layer boot to 5.06, now plug a modern board in, odds are you'll be hitting it with 5.4 or so, and that's not good.
Please don't take the advice of anyone who claims PC supplies work fine for them - maybe they do, maybe they don't - you're stuck with whatever setting it has however, and the price differential between a good quality 2nd hand (or new!) arcade PSU and a PC PSU is less than the cost of a PS2 game, and certainly less than the cost of a PC.
I've restored many arcade machines, and had a collection of PCBs second only to the madness of Shou-sama, one thing I learned is not to take chances with power supplies..
Although I understand your point (mostly agree) I have to say I never had to adjust the voltage in my cabinet for any modern PCB (post '95). I also never had any problems with PC power supplies and I used many. But then, I never had any real old PCBs and I will never do .bloodflowers wrote: Adjustable 5v is incredibly important.
And the Jameco power supply is for my home Neo Geo MVS setup. Since he was referring to 'custom build JAMMA systems' I thought his question went into that direction?
I bought myself a new cabinet which does not even has connection for -5V at the JAMMA edge! Linky!cool thanks, since it outputs +5 and +12 am I going to have to do something to make a -5 ?
Greets
Dennis