[Àû¿ë´ë»ó: DOSBox-x]

If set, VESA BIOS SVGA modes will be set to map
128KB of video memory to A0000-BFFFF instead of
64KB at A0000-AFFFF. This does not affect the SVGA window size or granularity.

Some games or demoscene productions
assume that they can render into the next SVGA
window/bank by writing to video memory beyond
the current SVGA window address and will not
appear correctly without this option.