I installed the Color DMD kit... pretty simple to do, really. When I turn on the machine, it refuses to boot. I can press the menu button on the Color DMD board and the firmware info comes up on the new display.
After tinkering around, I found that if I disconnect the ribbon that runs from the CPU/Sound board to the Stern display board, the game boots fine. If I then CAREFULLY reconnect the ribbon, the display comes up and acts exactly as expected.
Any ideas on what to check or what might cause this behavior? I have a LOTR too so there are 'spare' boards here for me to swap and experiment with but I wanted to reach out the community first.
Any help would be appreciated. For the record, the game was running perfectly fine before I swapped the display.
EDIT: L204 on Power Driver is blinking until I disconnect the ribbon running between the CPU/Sound board and the display board. As soon as I disconnect, the L204 goes solid and the game boots. As stated before, if I then carefully reconnect the ribbon, the display starts working correctly and the game is fully playable.