dreamcast no signal

[salvatore]

hi all and sorry for my bad english, the question is
i have buy 1 DC on ebay and after i have had no signal (black screen after 2h of play) then i have buy a new MB from ebay have install that and i have play same hours but while playing i still got black screen and no signal. i tried various cables (rgb hd adapter) but always black screen.
what could happen? likely that after a few hours it overheats and the motherboards are broken? now I no longer have the dreamcast and I think I don't buy any more from ebay

thanks

[Motoracer5]

I would guess the power supply board

[salvatore]

yes i have try that too i have buy a pico PSU

ps
just replaced the MB it worked for a couple of hours, but then nothing more. the same defect of the other motherboard, but does the HD adapter create problems for the motherboards?

[bshi02]

I think the largest capacitor in dreamcast's PSU need to be replaced.

I have played sega saturn But after some years later, It display only black screen after it display SEGA logos..I replaced the largest capacitor which located next to male connector of power cord in saturn's PSU,And it works well still now.