Naomi main board differences

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OldFoo

Naomi main board differences

Post by OldFoo »

I read somewhere that the early metal cage Naomi's have some component differences to the later plastic cased ones. My questions pertain to House of the Dead 2 in particular. I'm planning on making a setup to play all the gun games, but I understand that HOTD2 won't run on the plastic case Naomi's. Can anyone elaborate on this?



I know there's a dedicated BIOS for HOTD2, and was hoping that I could dual mod a Naomi to swap between HOTD2 and Japan BIOS chips to run all 5 gun games on one main board.



I have a white Naomi and I've just bought a metal World Series cage for a pretty good price on eBay for a spare and to see about running HOTD2, although it'll be a while before I can afford to buy an HOTD2 cart. Any information would be appreciated.



Another question is what the small 'relay' board is for. It looks to have 12v going to it, but I have no idea what it's for or if it's needed. It's called a 'condenser board' in the schematics.
OldFoo

Post by OldFoo »

Update:

I took a metal caged Naomi and put it in a plastic case. A friend helped me out with the dual bios mod, so now I can flip a switch between HOTD2 bios and the Japanese H bios.



After hearing that the metal cage Naomi's are physically larger or that they have additional graphics chips, the truth appears to be in the MAME driver files where it states that the early boards use a different revision of the graphics chip.



You can distinguish the early boards by the 'Made in Japan' stamp and by a large heatsink on the left side of the board. The metal and plastic cases are interchangeable. I put the HOTD2 cart into a cart case from Derby Club, so cart cases are swappable as well. Cart cases and dimm units will not physically fit in a metal cage, although they do work with the main board.
OldFoo

Post by OldFoo »

Did you have a read of this thread..



http://www.sega-naomi.com/forum/viewtop ... ght=hollie



It's the Hollie chip that's custom for F355/HOTD2
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