I had the same problem as you. Black screen is not good and suggest some major hardware fault.
The diagnosis was corrosion of the motherboard: acid and water.
I sent the motherboard for repair to a guy in New Zealand. He fixed it and it still works.
Last I heard was he was in in Antarctica!
Anthony Hoffman I think his name was. Last email I have was :ahoffman@clear.net.nz
Castellen is Anthony Hoffman (2 posts above) :-)
