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<topic xml:lang="en-us" id="customvesa">
  <title>Custom VESA Resolutions</title>
  
  <body>
    <p>Apart from the standard VESA resolutions, the <ph conkeyref="vbox-conkeyref-phrases/product-name"/> VESA BIOS
      enables you to add up to 16 custom video modes which will be reported to the guest operating system. When using
      Windows guests with the <ph conkeyref="vbox-conkeyref-phrases/product-name"/> Guest Additions, a custom graphics
      driver will be used instead of the fallback VESA solution so this information does not apply. </p>
    <p>Additional video modes can be configured for each VM using the extra data facility. The extra data key is called
        <codeph>CustomVideoMode<varname>x</varname>
      </codeph> with <varname>x</varname> being a number from 1 to 16. Please note that modes will be read from 1 until
      either the following number is not defined or 16 is reached. The following example adds a video mode that
      corresponds to the native display resolution of many notebook computers: </p>
    <pre xml:space="preserve">$ VBoxManage setextradata <varname>VM-name</varname> "CustomVideoMode1" "1400x1050x16"</pre>
    <p>The VESA mode IDs for custom video modes start at <codeph>0x160</codeph>. In order to use the above defined
      custom video mode, the following command line has to be supplied to Linux: </p>
    <pre xml:space="preserve">vga = 0x200 | 0x160
vga = 864</pre>
    <p>For guest operating systems with <ph conkeyref="vbox-conkeyref-phrases/product-name"/> Guest Additions, a custom
      video mode can be set using the video mode hint feature. </p>
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