No log.txt so can't see potentially important info You can try changing Hide Desktop to No (Setup Wizard> Display Settings), but that is just a shot in the dark. Your problem may lie deeper. To help us out can you confirm the following: Do the offending games work in MameUI outside of GameEx? If no, do you have the latest DX for your system installed? And do you have the latest drivers for your GPU installed? Yes to above but, still get black screen - does your romset match your version of MAME? The two must be in tandem, as one, peas in a pod, Romeo and Juliet, OK i know enough analogies when i seem em but you get my point. Admittedly i've never experienced any black screen issues except when: 1) My firewall kicks in and i can't see the prompt (again it would be persistent, not with some and not others), and 2) When i fail and enter a wrong path somewhere EDIT - Aha! Found another setting that may have some influence. Try changing: RunFullScreenInWindow=true to RunFullScreenInWindow=false using Setup Wizard> Display Settings> Full Screen Windowed = Disabled One of the assortment of options will help you out surely Yes, Yes & Yes dammit! - Run GameEx, as soon as you get a black screen through MAME, quit, then post us your log.txt