Naomi 1 won't work with NetDimm

[DJLC]

I got a mystery here. I have a Naomi 1 board that I'm trying to get to work with a NetDimm Board. The Netdimm will not load on this Naomi, it's just a black screen. No error comes up.

Here is what I've tried:

The Naomi works with regular carts.

The Naomi will boot with the NetDimm in GD rom mode.

The Naomi has multi bios and I've tries swapping the bios with known working ones.

The NetDimm works in other Naomi 1&2s.

I've tried swapping around the Zero Key on the Netdimm.

I've put in a new SuperCap and there was no damage under the old one.

I checked the Naomi with a different known working filter board.

I am out of ideas to check. I've swapped around everything I can think of but the main culprit appears the be the Naomi Mobo itself.

Here are some pics of the unit, does anythink look weird?

https://imgur.com/gallery/XXOhDByL

Anyone got any ideas?

 

[mathieulh]

Either you have a power delivery issue (bad/not properly tuned JVS PSU, faulty capacitor...) or one of the buffer chips on the naomi board is dead.

 

[DJLC]

Ive tried a few different PSUs (because I've had this in a few different cabs) for testing so it has to be a buffer chip.

Is this something that can be easily replaced?

 

[Trol]

Which carts will run ok on this board?
I had an N1 which wouldn't run Virtua Tennis, but ran Virtua Soccer fine... never found a solution for it. Only thing I know for sure, it was a motherboard problem.

 

[DJLC]

I've only tried GGX on it but I'll try MVC2, that's the only other cart I have

 

[MetalliC]

I had an N1 which wouldn't run Virtua Tennis, but ran Virtua Soccer fine... never found a solution for it. Only thing I know for sure, it was a motherboard problem.

if it was Virtua Tennis 2 - it smells like broken CN1 connector.

PS: older type carts uses CN3 bus, while newer types (and I think DIMM too) uses CN1 bus.
so, if one of connectors broken - mobo may work fine with one type carts but doesn't work at all with another.

 

[DJLC]

Does the NetDimm use a different connection when working in GD-Rom mode? The GD-Rom mode works fine on this Mobo