    AST RESEARCH, INC.         TECHNICAL BULLETIN #0848               07-29-93

                       POWER EXEC SIMULTANEOUS DISPLAY DROP OUT

    PROBLEM:       The customer experiences a problem on their PowerExec 3/25SL
                   and 4/25SL notebooks, when attempting to run simultaneous
                   video (FN + F5) with an external monitor.  When they used the
                   ALT-TAB keys to switch form a Windows application to a DOS
                   window, one of the displays would drop out.

    CAUSE:         When Windows is started with both the external CRT and the LCD
                   screens active (Both displays are on), both screens will
                   operate properly.

                   When the simultaneous display is initiated after Windows has
                   been loaded, the original video configuration will be present
                   when you ALT-TAB between Windows and DOS applications.

    SYSTEMS
    AFFECTED:      AST PowerExec Notebook family.

    SOLUTION:      Configure the system for simultaneous display prior to loading
                   Windows.