I've got a very similar issue which I can't figure out.
In my case I'm trying to run Ikaruga and keep getting the following Error:
ERROR 04
BOARD MALFUNCTIONING.
The two other GD-ROM games I own work fine (Border Down and Capcom Vs. SNK : Millennium Fight 2000 Pro).
The RAM TEST and the DIMM BOARD test all pass with GOOD status.
I tried cleaning the GDROM, even tried an older BIOS.
So, I can't figure out why I'm getting this message...
Naomi 1 with GD ROM:
I/O board: 837-13551-92
BIOS: EPR-21576H
Any ideas?


