[nmglug] xfce mint sleeping?

My new Mint 19.2 install if xfce mint is kind of locking up. Seems to be some sort of power management thing.  It responds to ping.  caps-lock and num-lock change keyboard lights, but screen is dark, and it does not respond to ssh. Logs seem fairly clean.  It seems to be doing cron jobs all night, but just won't respond to keyboard or ssh. It seems to show a clean restart when I get frustrated and touch the power button. Any ideas?  Any idea what to look for in a log to see what it is doing? aaron