The Nx Desktop client requires a computer which supports OpenGL 2.1 or higher. Typically, this is not an issue, but in some cases, a need arises to launch the desktop client application on computers with limited graphics capabilities.

For example, in the case of using a virtual machine, or a server PC with limited graphics capabilities are typical examples where OpenGL may not be supported.

To circumvent this limitation, there is a way to emulate the necessary graphics functions through the CPU, which allows running the desktop client application on hardware devices if the client application is installed on any Windows x64 OS version.

Alternatively, a VMware virtual machine with VMware tools installed does support OpenGL (see our support article Virtual Machines for details).

IMPORTANT:

Emulation is an experimental feature that isn’t tested for each build.
Emulation might not work on your hardware.
When using this method, what you are really doing is transferring the computing load that would normally be done by a GPU to the CPU. This will cause your CPU usage to rise significantly. Close the Desktop Client as soon as you are finished with your task to return your CPU load to normal.
Avoid CPU intensive tasks, such as exporting footage or turning on motion detection for high resolution streams.
We do not recommend using this emulation method unless it is absolutely required, such as for administration tasks.

How to emulate the GPU using your CPU

Download the OpenGL emulation library (version 23.1.0). To decide which package you need, MSVC or MinGW, please check the readme.md documentation.
Extract the archive to a folder.
Copy opengl32.dll, libglapi.dll, and libgallium_wgl.dll files.
Past the copied files to the folder where the Nx Desktop executable is located.

Normal installations:
```
C:\Program Files\Network Optix\Nx Witness\Client\<version_number>
```
Compatibility version and in-client update installations:
```
C:\Users\%USERNAME%\AppData\Local\Network Optix\client\default\<version_number>
```
Note: version_number = your Nx Desktop version number
Open CMD and enter this command to create the environment variable to enable OpenGL software rendering:
```
setx GALLIUM_DRIVER llvmpipe
```
(Re)start the Nx Desktop client.

How to emulate the GPU using your CPU

Normal installations:

Compatibility version and in-client update installations:

Related articles