Modify and use your screen resolutions

October 2016

Sometimes you find that your screen resolution is too high, you try to change it, but it becomes too small. So it would be interesting to develop a resolution that does not appear in the list of pre-defined resolutions. This is possible by modifying the registry on either Windows XP or Vista.

First, make sure you have a CRT monitor, not an LCD flat screen, because it gives a poor quality display if you specify a different resolution than supported.

Before starting the registry changes, it is preferable to make a backup of the registry in order to restore it if it goes wrong.
  • Open the Registry Editor: Start Menu> Run (or Windows key + R)
  • Type regedit and click OK.
  • Open the following keys:HKEY_CURRENT_CONFIG\System\CurrentControlSet\Control\VIDEO
    • Under XP:
      • Open the subkey: Mon22446688
    • On Vista:
      • Open the subkey: {64A39CFB-0C4F-4C63-8A22-C0CAD6EB9E5A}
  • If you can not find the key: Mon10000000, continue by opening the key 0000
  • Double-click the value DefaultSettings.Xresolution
  • Check the box: Decimal
  • Edit the fields of data by the desired horizontal resolution. This value represents the number of pixels on each line on your screen, it must be divisible by four. Take for example the value 1000.
  • Double-click the value: DefaultSettings.Yresolution
  • Check the box: Decimal
  • Edit the fields of data by the vertical resolution. This value must be equal to 3 / 4 the previous value. So 750 for our example.
  • Close the registry and restart your PC.

Related :

This document entitled « Modify and use your screen resolutions » from CCM ( is made available under the Creative Commons license. You can copy, modify copies of this page, under the conditions stipulated by the license, as this note appears clearly.