It sounds like you don't have the external pass-through (loop back) cable hooked up properly. I would hook it up like this:

Video card <- pass-through -> Monster 3D input,
Monster 3D output <- pass-through -> DVD decoder,
the DVD decoder is then connected to your monitor.

This is the way most DVD decoders (inlay cards) are connected as far as I have seen. Did you buy the full retail kit or did you buy the parts seperately? They may have forgotten to give you the proper cables if puchased seperate.

[This message has been edited by Menace (edited September 10, 1999).]