This has been bugging me for a while as I notice there is now way to force powermizer to always use level 3 even after a reboot. Luckily I found a handy youtube video showing how to do this simply by adding an extra line to a file. Here it is:  http://www.youtube.com/watch?v=DEOBZWOUizc It's a simple matter of adding a single line of text: Option "RegistryDwords" "PerfLevelSrc=0x3322; PowerMizerDefaultAC=0x1" to the following file: xorg.conf located at: /etc/X11 Please note that this line is added to the "device" part of the file eg Section "Device"     Identifier     "Device0"     Driver         "nvidia" Option "RegistryDwords" "PerfLevelSrc=0x3322; PowerMizerDefaultAC=0x1"     VendorName     "NVIDIA Corporation" EndSection The net result of this is that when you restart and look at nvidia-settings you get this: and it stays on level 3