This is a bit hacky IMO. It works by leveraging a quirky nvidia-settings behavior that forces the gpu to full power for several seconds when nvidia-settings is loaded. Ideally you shouldn't have to burden your cpu with unnecessary load in this way. Here's what's worked for me (using the latest 185.19 beta):
Originally Posted by SketchyClown
Add the following option to your xorg.conf file under the device section:
This places the gpu in max perf mode when on AC, and reverts to gpu scaling on battery.
Option "RegistryDwords" "PowerMizerEnable=0x1; PerfLevelSrc=0x3322; PowerMizerDefaultAC=0x1"