How to see everything in the NVRAM I know you can show the contents of the NVRAM with sudo nvram -x -p, but doing that doesn't seem to list everything. I say this because I just had an issue with the resolution of my screen at boot, resetting the NVRAM fixed it. However, I compared the output of that command before and after clearing the NVRAM, and it is identical. Are there more variables in there that can't be seen with the traditional sudo nvram -x -p? If so, can they be seen with another method?
In a Terminal type man nvram and press: enter

You'll see that the -p option states:


  Print all of the firmware variables.


Therefore whatever it prints, is what's stored in NVRAM.

There should not be any hidden variables, however the output for some variables may not be in what's generally considered as human readable format.