I ran into an annoying interesting issue after installing Ubuntu 16.04. Even after adding the ppa and installing the latest Nvidia drivers, the Display tool couldn't detect any information about my primary monitor or the other two attached.

Running xrandr only showed one low resolution mode for the default monitor.

Running lshw -C display showed the two missing monitors as "UNCLAIMED".

Initially I tried manually adding the display modes for the monitor to xrandr using gtf to generate the Mode Line. But even with the new mode I still couldn't change to the correct resolution.

A lot of people seemed to have had similar issues and lot of the recommendations were to purge and reinstall various drivers.

In my case the issue ended up being that Secure Boot was blocking the the third party tools from accessing the hardware.

I discovered this after purging the drivers I had and reinstalling nvidia-370 driver. The installer alerted me to the issue and was able to use a shim to disable secure boot, although I ended up making the change myself in the BIOS.

If you are having a similar issue here are the steps to resolve it.

sudo apt-get purge nvidia-*

sudo add-apt-repository ppa:graphics-drivers/ppa

sudo apt-get update

sudo apt-get install nvidia-370

Then follow the directions to allow the program to disable Secure Boot or do so yourself in the BIOS.