My setup's are all 15khz monitors. So that isn't it either.I have gotten neogeo battle collisium and dolphin blue to run with no issues when in 15khz mode on my naomi 2. But if i switch to 31khz mode, i just get a black screen. I am using a cf card reader from mitsurugi. so far my only naomi game runs fine in both 15khz and 31khz (marvel vs capcom 2) so maybe its as simple as the khz setting?