If it was not packaged right then you never know.

Does the green light come one? Is the IIgs putting out a good video signal?

If every thing is set to black from the control pannel on the IIgs then it is like the black out virus. Have to bring up the control pannel then hit 2 then then 2 again and again or something like that. To set everything to standard defaults. There is a few other things but it would be easier over the phone.

Take Care