NX has always required accelerated graphics, which makes a graphical processing unit (GPU) essential when running NX.
Previously, if a GPU was not present, the session would still run and, depending on the commands that are used may even appear to have been a successful session. In those cases, a message would appear in the syslog file about the lack of a GPU being present, but the user often did not see this information, so it may have appeared that the GPU was only recommended, instead of required.
Advancements in the graphics libraries used in NX now require the use of a GPU.
Starting with the June 2023 release, if a GPU is not present NX displays the following message to the user, which is also written to the syslog file.
If you ignore this message and continue to run the NX session, it could lead to undefined behavior or error messages.
The GPU requirement is for interactive or 'headless' image capture sessions. Other 'headless' NX batch sessions will continue to function as before.
The list of currently supported hardware and graphics cards can be found on Hardware and Software Certifications.
https://support.sw.siemens.com/en-US/product/209349590/knowledge-base/PL8017193
Click NX-Graphics-Certification-Table to open a spreadsheet that has tabs for supported systems and graphics.