I just upgraded from Windows 7 using the original EVGA Precision with an included installation of RivaTuner. With the addition of a "1337" parameter in the configuration file, I could specify the fans running normally when not gaming - and they would switch to another profile once a 3D game started.  So I had essentially automatic fan control that would spin up aggressively when gaming, and spin back down when I exited the game.
 
Upgraded to Windows 10 and had to uninstall the incompatible old EVGA Precision + RivaTuner combination - and installed EVGA Precision X1.  While I have figured out how to set profiles (it's still confusing!), I have no idea how to have Precision automatically choose a 3D (gaming) profile or a casual 2D (non-gaming) profile.
 
This worked perfectly with the old version.  But with X1, it's unclear if it's even possible to automatically switch from one profile to another based on whether I'm gaming or not.  Any help or insights?

Man, bob16314 - you really hooked me up in no time at all.  I know you've been here on these forums for a long time, so I really appreciate your quick reply and expertise.
 
I had unnecessarily removed Precision 4.2.1 along with the incompatible version of RTSS.  Reinstalled thanks to your link - and restored all of its settings from a recent backup to get my profiles back (before the upgrade to Win10), installed the latest RTSS and everything's working PERFECTLY!
 
Thanks for setting me straight and quickly summarizing the different Precision variants.  Cheers!