There are a couple of ways to see if the option is installed. 1. If the module is not installed in the mainframe, look at the rear of the module .  If there is a small board mounted above the main board, the option is installed. 2.  You can tell if the DVG1 has option S1 by clicking MODULE PARAMETERS in the DVG1 menu structure. If SDI shows up, the S1 option is installed.