/sys$common/syshlp/helplib.hlb Sys Parameters, CHANNELCNT  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    CHANNELCNT specifies the number of permanent I/O channels
    available to the system.

    This special parameter is used by Compaq and is subject to
    change. Do not change this parameter unless Compaq recommends
    that you do so.