Naomi 2 Repair?

PCB problems and fixes
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Brettster
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Naomi 2 Repair?

Post by Brettster »

I have a faulty Naomi 2 Motherboard. powers up, has a green and red LED but there is no sound or picture, just a black screen on the monitor
I found that the little cap near the button cell battery had leaked so this has been removed and the electrolite cleaned up. it didnt look like any of the traces were corroded and i've tested all the points affected for continuity they seem ok
N2 Mobo.jpg
can anyone suggest anything else i could try ?

thanks
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Layer
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Re: Naomi 2 Repair?

Post by Layer »

If you can translate from french to english, a kind of log to help to check/repair has been done : http://www.gamoover.net/Forums/index.ph ... #msg535924
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leonardoliveira
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Re: Naomi 2 Repair?

Post by leonardoliveira »

I believe that's not a normal cap, but the supercap which allows you to replace the socketed button cell battery (CR2032) without losing the bookeeping/calendar data.
Naomi 2:

Ecran noir
-Bios corrompu ou non present
-Problemes CPU plus particulierement dut au BGA (arrive trèèèèèèèèèèès rarement.changer les mains rams peuvent la faire booter)
-supercap ( à changer ou qui à coulé.Pose moins de soucis que sur N1,pas trop de composant aux alentours)
-ventilateurs CPU ne fonctionnant pas
- 1 ou 2 Mains RAM (IC106 et IC107) est/sont morte(s)
Hopefully I understood it well:

Naomi 2:

Black screen
-BIOS corrupted or not present
-Problems with the CPU more particularly at the BGA (veeeeeeery rare fault. changing the main RAMs may make it boot)
-Supercap (replace or remove. not too worrisome as there's not too many parts close by)
-Fans not working
-1 or 2 main RAM (IC106 and IC107) are dead.

Very nice piece of repair advice, btw
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invzim
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Re: Naomi 2 Repair?

Post by invzim »

Yes, was about to suggest the fans - if they are not connected/working it won't boot.
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Brettster
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Re: Naomi 2 Repair?

Post by Brettster »

Thanks for the replies
All 3 fans are working fine
I do have another Naomi 2 so I may try swapping the bios rom over
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purplec
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Re: Naomi 2 Repair?

Post by purplec »

Is it not the altera chip?
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leonardoliveira
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Re: Naomi 2 Repair?

Post by leonardoliveira »

The Altera chip is sold blank. You have a tiny Altera 8 pin chip which loads it's configuration on power on, then it works properly as part of the Naomi board.

What make you think it's faulty?
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Brettster
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Re: Naomi 2 Repair?

Post by Brettster »

Swapping the bios chips didn't help
Still nothing
Actually the monitor doesn't detect a signal with the broken one
The working one starts with a black screen but you can see the monitor detect it and turns off the no signal message almost as soon as I plug it in

Also tried swapping the fans :(
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purplec
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Re: Naomi 2 Repair?

Post by purplec »

leonardoliveira wrote:The Altera chip is sold blank. You have a tiny Altera 8 pin chip which loads it's configuration on power on, then it works properly as part of the Naomi board.

What make you think it's faulty?
Read a repair by channelmaniac I think that said this can be a cause of failure at times
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denson
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Re: Naomi 2 Repair?

Post by denson »

I'm not really up on this sort of thing, but would replacing the filter board help? I had to replace it on a Naomi 1 that showed no picture and now works fine... Could try swapping it with your working one and see what happens? Like I say, I'm not really technically minded, but if it was the filter board you may be able to fix that? :shifty:
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andygeezer
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Re: Naomi 2 Repair?

Post by andygeezer »

Naomi2 are more prone to dying in shipping. Bga faults, amount of times those heat sink pull at the bga chips.

Hikaru is the worst offender.
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Brettster
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Re: Naomi 2 Repair?

Post by Brettster »

Hi Andy
can you repair them?
I have tried a different filter board too
is it work swapping the 8 pin chip that programs the big altera chips with my working one?
I dont want to ruin another N2 board
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leonardoliveira
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Re: Naomi 2 Repair?

Post by leonardoliveira »

andygeezer wrote:Naomi2 are more prone to dying in shipping. Bga faults, amount of times those heat sink pull at the bga chips.

Hikaru is the worst offender.
I've seen that happen. Extremely sad sight ! :cry:

The problem is, the HOLLY chip (GPU) use a NEC packaging where the chip is bonded to a flexible heat resistant conductive board then glued with thermal glue to a square copper sheet which is then painted black on the exposed side. That copper sheet is then attached to the heatsink/fan assembly. The only thing holding the heatsink/fan assembly in place is the flexible board and the HOLLY die. As the shipping jams and bumps the board violently the poor HOLLY chip is ripped apart from it's mounting by the laws of physics. And you end with a dead Naomi2 board. :cry:
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Brettster
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Re: Naomi 2 Repair?

Post by Brettster »

That sounds pretty terminal!! The board was in the cabinet whe it was shipped but I guess it could have had some handling on and off the truck
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Re: Naomi 2 Repair?

Post by Aaronr33 »

Brettster did you ever figure out why your Naomi 2 does.not.boot?

I am having same issue. Doesn't boot and get black screen, vga monitor doesn't see any signal.
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