How do I change the resolution of an Amazon EC2 Windows Machine?

Disclaimer: TightVNC is not secure, so if security is an issue, you may need to find a different approach. The whole process will take only a few minutes, so the security hole is small, but there nonetheless.

1. Install TightVNC Server on the EC2 instance so you can log into the console
2. Disconnect all user remote desktop sessions and return the session to console
3. Use the TightVNC Viewer to log into the EC2 instance console, ensuring port 5900 is open for that connection

4. 

   • Right-click on the desktop and select "Screen resolution"
   • Select "Advanced settings"
   • Select "List All Modes"
   • Select a higher resolution

You can change the screen resolution by modifying two registry values. These two values are: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Video\GUID\0000\DefaultSettings.XResolution HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Video\GUID\0000\DefaultSettings.YResolution Where GUID is a randomly generated GUID.

You can actually specify any XResolution and YResolution value as long as they are hexadecimal.

Note: In the case of a CRT monitor specifying an absurd resolution might damage your monitor. In the case of a LCD monitor your monitor might not show any user interface anymore. A good way to change your Screen resolution is to write down the amount of pixels you want to fill your screen width with (this is the XResolution) and the amount of pixels you want on your screen height (the YResolution). The Windows calculator (not available in Server Core , you will have to find another computer or a hardware advanced calculator) offers an easy way to convert decimal amounts to hexadecimal amounts. You can then use these values to modify the corresponding registry values. A restart will make your preferred screen resolution meet reality.

The color depth used on your monitor is captured in the following registry value: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Video\GUID\0000\DefaultSettings.BitsPerPel On my box this hexadecimal value was set to 0x00000008 (8) which meant my screen used an 8 bit color depth. (256 colors) Changing it to 16 bits (0x00000010) will show 65536 colors (High Colors) Other values that are typically available are 24 bits (0x00000018) and 32 bits (0x00000020).

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