another installing upgrade question

Hi,

I read in the archive that I can install my Studio MX 2004 upgrade on a new
computer without having to install the previous version (Studio MX). All I need
is my serial #. How many versions back must I have #'s for. My MX was an
upgrade from DW 4. I have the Studio MX #'s but can't locate the DW 4 disk.

Thanks,

Stephen Scheaffer