Power management tweak didn't fix it.
I rolled back to v378.66 (Feburary 2017) and it appears to be working.
I am trying to run the game, however, right after the splash screen I am getting
"Video driver has crashed and was reset! Make sure your video drivers are up to date. Exiting..."
I am running a GTX 970 with driver version #384.76 (Latest as of today, I believe).
I dont see any log file output for further troubleshooting - any ideas?