I have read from 1 source that a rev D motherboard is not compatible with the Naomi GD-rom system, but I have not been able to confirm this with any other source.  
Is a Rev D motherboard incompatible with a dimm and gdrom drive?
			
			
									
									
						Naomi Motherboard Rev D
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				OldFoo
 
That is correct. It must be rev. E or later to support the GD-ROM system. Here is a reference
list from the forum's main site-->Naomi BIOS list<--
			
			
									
									
						list from the forum's main site-->Naomi BIOS list<--
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				OldFoo