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KC-Slater

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HI everyone,

I am having issues with using my Naomi outside of my previous cab (Naomi Universal.) Unfortunately I no longer have my cab, so I can't completely rule out that it's not the Naomi mainboard.

I am using RGB's supergun. I can confirm this is working without issue, as I was using it with my MVS before and after trying it with my Naomi.

I can confirm that it was working with a Netboot setup as well with a couple of cartridges inside the cab without issue, but when I try to use it with my PVM, Plasma or LCD (with or without OSSC scaler) I am not getting any image on screen, or hearing any game audio.

I have tried with both an ATX PSU with the proper cable connector as well with a switchable PSU via the Capcom I/O, and I still don't see anything on screen. Voltages seem okay, with 5V up to 5.1v having been tested.

I can hear the fan(s) coming on, and I feel air moving through the vents. I can also see two lights inside illuminated -- one green and one red.

I have tried with both just a cart and with the NetDimm.

I have tried both all dip switches off, and dip switch 1 on, and with video directly outputted form the Naomi, and through the Capcom I/O JAMMA to my HAS v3 supergun.

I'm at a loss. Does anyone think they can diagnose this, or give me some advice to see what's wrong?
 
With dip1 off and good power you should get video on a normal vga monitor directly from the NAOMI. If not you can humor yourself and try a new BIOS. After that you're getting into component level BS. Have a look and make sure your supercap isn't leaking while you're at it.
 
Thanks @skate323k137.

I'll try again tonight. If the BIOS is not seated properly or is bad, would that be reason enough for NOTHING to appear on screen? (This is in the realm of possibility, as I think I may have swapped BIOS chips at some point...)

Also, can anyone explain if the different coloured lights inside the mainboard housing mean anything?
 
Correct, if the BIOS is bad or seated incorrectly, you will get no video at all. The system cannot boot at all without a BIOS.
 
I've tried a couple of BIOS chips that I have, and none seem to work. To complicate things further, I accidentally broke one of the pins off of the third BIOS chip that I thought was bound to work for sure, before I got to test it!

I opened up the casing and looked for any dirt, traces of blown caps, and everything look suspiciously clean. Even the case wasn't too dusty/grimy. I gave it a clean with some compressed air, and cleaned the fans as well.

So at this point I'm still holding out hope that it's just an issue with a BIOS, maybe a power issue, or perhaps the NAOMI is just being picky about my display. I'm trying to use it with an old BENQ LCD monitor, and have tried it with 15k output to the HAS v3 supergun to my PVM without any luck. Can anyone confirm as to whether or not NAOMIs are particular about which computer monitors they like to work with?
 
run it with the top off and make sure the small fan(s) sin o.k.
there is a small chip monitoring the tacho output from the fan(s) and if the rpm is too low then the power will be cut from the main chips to protect them.
unplug and re-plug the fans too - incase the contact is dirty.
 
I tried with the top of the case off -- both fans are spinning and both the green and red light are on and stay on.

I did notice that one of the fans' wires is hot glued to the top of a chip -- is this normal? It looks like it was intentionally done.

I might just bite the bullet and order another BIOS. Any suggestions which one to grab and where to do so?
 
I have a dead Naomi 2 that does the same thing, the fans spin and the lights are on but no one is home.
it would be quite rare for a bios to go, but not impossible what seems to kill most of the Naomi's is the super cap leaking and eroding the copper traces which are usually close to or under the Bios socket
post up a nice high quality photo of the pcb.
might be able to see something
 
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