I have a South Park that shows the display on startup (splash screen) but then goes dark after that. I had been told U201 on the CPU board was likely the culprit and replaced it but still seeing this. I've reseatted connectors and double checked ribbon cables. I've even swapped the long ribbon cable that sometimes get pinched and still no luck.

Everything worked fine until I replaced one of the transistors on the power board.

Any thoughts or suggestions appreciated.

Thanks
Chris

It does seem unrelated so perhaps entirely a coincidence. It was Q7 - flash pops.

I've checked the ribbon cables multiple times.

At this point I've swapped the CPU, display controller board and all three ribbon cables from a working Godzilla with no luck. Will be trying the power board next (probably later tonight or tomorrow).