    AST RESEARCH, INC.         TECHNICAL BULLETIN #0685                  05-24-91

                      THE SUPER VGA MONITOR WITH AST VGA ADAPTERS

    In January of 1991, the "dot clock" frequency of the AST Super VGA monitor
    (part number 500783-XXX) became 36 megahertz in order to comply with industry
    standards.  This is designated by the characters "36MHZ" on the back of the
    monitor.

    This change causes an incompatibility with AST VGA display adapters in
    certain display modes.  The symptoms appear when the "Enhanced Text Mode"
    (132 characters by 25 lines or 132 characters by 43 lines) is chosen for the
    display mode.  The monitor will display only horizontal scan lines instead of
    readable text.

    The following table describes the revision level of a given VGA display
    adapter required to maintain compatibility with the "36MHz" Super VGA
    adapter.

    Description              Part Number          Revision Level

    VGA Adapter (8 bit)      202249-005            C or above
    VGA Plus Adapter         202262-003            D or above
    CUPID System Board       202360-001            S or above
    DSX-16 VGA Adapter       20H004-001            X4 or above