UPDATE TO UBUNTU 18.04--

I updated after configuring the release upgrade from the keyboard.  I then connected from remote via SSH, and repeated the steps outlined above.  The update completed without a system hangup, and then rebooted.

On reboot, nvOC did not start the miner.  I issued "nvOC start", and received this response:

       "m1@m1-desktop:~$/home/m1/NVOC/mining/nvOC start
        Restarting nvOC tasks....

        Unable to init server: Could not connect: Connection refused
        # Failed to parse arguments: Cannot open display:
       m1@m1-desktop:~$"

I will go into the miner directory and set up a standalone start script, but I would like to set the system straight so that it can talk to itself.  Any suggestions?       --scryptr