listing all the environment variables understood by houdini from ‘hconfig -a’, I've discovered the ‘FPS’ one.
However, trying to set it - with 25 - from a command file ( in a 456.cmd on our HSITE ) I get the following error in the Textport once houdini launched:
MHoudini/houdini7.0/scripts/456.cmd (32): Invalid variable name (FPS)