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THESE ARE BACK IN STOCK! WON'T RUN OUT OF PARTS FOR A LONG TIME!

Price is $30

This high-quality, hand-crimped adapter will allow you to power your entire Naomi setup including the main pcb, DIMM or NetDIMM, and GD-rom or CF Kit (with separate cable) using a standard PC ATX power supply. This adapter is wired by default to power on automatically when you power the ATX supply but there is an option available for leads to allow you to mount an external power button. This adapter runs a wire from EVERY SINGLE 5v, 12v. 3.3v and Ground connection on the 24-pin ATX connector for more robust voltage control to prevent starving the Naomi of the necessary power.

Adapter shown is wired for auto-power when ATX power button is flipped on

tDbTlkP.jpg
 
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The ONLY downside I found is not being able to adjust the 3.3v as the ATX power supply I was using had some kind of variable control built in. So if you use an ATX make sure you get one that isn't self regulating and has a constant power flow.

I would love a mod to be able to adjust the +5, +3.3, and +12 VDC in addition to a digital display showing the voltages .. but that's allot of work.
 
The ONLY downside I found is not being able to adjust the 3.3v as the ATX power supply I was using had some kind of variable control built in. So if you use an ATX make sure you get one that isn't self regulating and has a constant power flow.

I would love a mod to be able to adjust the +5, +3.3, and +12 VDC in addition to a digital display showing the voltages .. but that's allot of work.
All very true. The preferred method is to use an adjustable supply. I've made these adapters before with mixed success. So many people ask about these that I decided to try a new version as an homage to the model 2 and 3 power wiring. Many of you may have noticed that Jasens Customs have been pushing his version on twitter hard lately. His version, though cheaper, is very similar to my old version. It uses the 20-pin ATX (as did my old version) connector and only uses the number of wires to match 1 to 1 how many are used by the two connectors on the Naomi. As I said earlier when I built mine this way I had mixed results and often would have resetting randomly and the dreaded Error 01 (not enough juice).

So instead I've switched to a 24-pin ATX connector. Most modern PC supplies have the 20-pin plus 4-pin that you put together to plug in at least. What this provides is an etra 3.3V, 12v, 5v, and Ground wire to use for more reliable amperage. My adapter now uses EVERY available 3.3v, 5v, 12v, and ground pin available on the main connector. So my adapter uses:

2 yellow wires for 12v
4 orange wires for 3.3v (important!!)
5 red wires for 5v
7 black wires for ground

I also connect the green wire to a ground pin for auto-power. If you want a power toggle switch connector then there would be a free hanging green and black wire.

Looking at the one from Jasen's customs he is using:

2 orange for 3.3v
2 red for 5v
1 yellow for 12v
6 black for ground

1 green and one black free hanging for power on/off.

He is using a thicker wire than I am now. My old design used the same gauge he is now. I found going up in gauge a bit and adding more points makes it more reliable. It was necessary to go down in the wire thickness (higher gauge = thinner wire. I know, confusing) so you can crimp multiple wires into one pin on the Naomi connector side.

The same adapter above ran my Naomi for 10-hours last night with no hiccups at all using the same old ATX supply that wouldn't boot the Naomi reliably with my old adapter. I feel really good about it.
 
Which AWG gauge do you use? I used 18AWG, which should be plenty when using 4 wires each for 3.3V and 5V.

Naomi (JVS) <-> ATX Adapter

Regardless - moar copper qualifies for an unconditional thumbsup! With proper cables, there is little to no use for tweaking voltages at the PSU side.
 
The ONLY downside I found is not being able to adjust the 3.3v as the ATX power supply I was using had some kind of variable control built in. So if you use an ATX make sure you get one that isn't self regulating and has a constant power flow.

I would love a mod to be able to adjust the +5, +3.3, and +12 VDC in addition to a digital display showing the voltages .. but that's allot of work.
All very true. The preferred method is to use an adjustable supply. I've made these adapters before with mixed success. So many people ask about these that I decided to try a new version as an homage to the model 2 and 3 power wiring. Many of you may have noticed that Jasens Customs have been pushing his version on twitter hard lately. His version, though cheaper, is very similar to my old version. It uses the 20-pin ATX (as did my old version) connector and only uses the number of wires to match 1 to 1 how many are used by the two connectors on the Naomi. As I said earlier when I built mine this way I had mixed results and often would have resetting randomly and the dreaded Error 01 (not enough juice).
So instead I've switched to a 24-pin ATX connector. Most modern PC supplies have the 20-pin plus 4-pin that you put together to plug in at least. What this provides is an etra 3.3V, 12v, 5v, and Ground wire to use for more reliable amperage. My adapter now uses EVERY available 3.3v, 5v, 12v, and ground pin available on the main connector. So my adapter uses:

2 yellow wires for 12v
4 orange wires for 3.3v (important!!)
5 red wires for 5v
7 black wires for ground

I also connect the green wire to a ground pin for auto-power. If you want a power toggle switch connector then there would be a free hanging green and black wire.

Looking at the one from Jasen's customs he is using:

2 orange for 3.3v
2 red for 5v
1 yellow for 12v
6 black for ground

1 green and one black free hanging for power on/off.

He is using a thicker wire than I am now. My old design used the same gauge he is now. I found going up in gauge a bit and adding more points makes it more reliable. It was necessary to go down in the wire thickness (higher gauge = thinner wire. I know, confusing) so you can crimp multiple wires into one pin on the Naomi connector side.

The same adapter above ran my Naomi for 10-hours last night with no hiccups at all using the same old ATX supply that wouldn't boot the Naomi reliably with my old adapter. I feel really good about it.
My issues mostley manifested when trying to run Atomiswave games and the Melty Blood games. On the ATX power supply these were hit or miss as to if they would run. Most of the time they would load to a black screen. However this was solved with a Sun power supply. For the longest time i thought some was wrong with my Naomi .. which was not the case.
 
Which AWG gauge do you use? I used 18AWG, which should be plenty when using 4 wires each for 3.3V and 5V.

Naomi (JVS) <-> ATX Adapter

Regardless - moar copper qualifies for an unconditional thumbsup! With proper cables, there is little to no use for tweaking voltages at the PSU side.
For this one I used 22awg but it's the best quality 22awg I've ever had. I might order 20awg from the same place I got this stuff from. It will still be small enough to crimp multiple wires together. I used 18awg with my older adapters and that is one reason why I had to use fewer wires before. Doing it this way is working way better than my old ones.
 
Totally agree ! Awesome quality cables. Highly recommended + fast shipping. Thanks!
 
Hello there, with my Naomi and NetDIMM setup this looks ideal, will be sending a PM. Cheers!
 
Question. When using this cable and a Capcom IO converter connected to JAMMA for audio/controls, Is it safer to turn the cab on first then the ATX? Or power up the Naomi and then the cab.

Or does it not matter really?
 
It shouldnt matter. Are you having issues?
 
No issues at all. Was just wondering if there was a right and wrong way.
 
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