When DirectDraw calls an application's EnumModesCallback callback function, the ddsCaps member of the associated DDSURFACEDESC or DDSURFACEDESC2 structure contains flags that reflect the mode being enumerated. You can expect DDSCAPS_MODEX for a Mode X mode or DDSCAPS_STANDARDVGAMODE for Mode 13. These flags are mutually exclusive. If neither of these bits is set, then the mode is a linear accelerated mode. This behavior also applies to the flags retrieved by the IDirectDraw7::GetDisplayMode method.

When DirectDraw calls an application's DirectDraw7.GetDisplayModesEnum method, the ddsCaps member of the associated DDSURFACEDESC2 type contains flags that reflect the mode being enumerated. You can expect DDSCAPS_MODEX for a Mode X mode or DDSCAPS_STANDARDVGAMODE for Mode 13. These flags are mutually exclusive. If neither of these bits is set, then the mode is a linear accelerated mode. This behavior also applies to the flags retrieved by the DirectDraw7.GetDisplayMode method.