VMS Help Sys Parameters, VECTOR_PROC  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    (VAX only) VECTOR_PROC controls loading of vector processing
    support code. By default, in a VAX vector processing system, the
    system automatically loads the vector processing support code
    at boot time. You can override the default behavior by setting
    the static system parameter VECTOR_PROC to one of the following
    values:

    Value  Result

    0      Do not load the vector processing support code, regardless
           of the system configuration.

    1      Load the vector processing support code if at least one
           vector-present processor exists. This is the default
           value.

    2      Load the vector processing support code if the system is
           vector-capable. This setting is most useful for a system
           in which processors have separate power supplies. With
           this setting, you can reconfigure a vector processor into
           the system without rebooting the operating system.

    3      Always load the vector processing support code.

    This parameter is not used on Alpha systems.