I recently bought 2 dreamcasts from a garage sale for pretty cheap. Unfortunately, one of them doesn't work, so I'm trying to fix it.

When I plug it in and turn the power on, the LED turns on and the fan spins up, but only for a moment, then it dies again. Turning the power off, and then on again does nothing (no light/fan), but if I unplug it and try again in a few minutes, the same thing occurs. Also the length of time that the fan/LED stay on appears random, sometimes almost too quick to see, and other times several seconds.

I've already tried removing the psu and cleaning/applying pressure to the pins that connect it to the mobo (as per the instructions in the thread "Dreamcast Reseting Problem - help") but that doesnt seem to have fixed it. Anyone got any ideas?

I have this exact same problem...does anyone know how to help?

Someone brought up this very issue on GameFAQs. That person couldn't fix the problem either, but he did get this system to power on normally when he removed the GD-ROM drive unit.

I don't have a system with that same problem or else I could conduct some tests. In his case it sounds like what was happening is that either part of the GD-ROM drive had failed and was disrupting the flow of power or that the power supply was no longer putting out enough voltage to run the system.