There is fairly recent problem with 17.04. I have always had my computer "Turn screen off when inactive for 30 minutes". The Lock button has always been off, and I don't require my password when waking from suspend.
This has always worked well. Moving the mouse or pressing a key wakes up the computer. Now if I leave the computer and come back later (>30 min), the screens are black as expected (I have dual screens). The problem is that I can't wake up the computer. I have to power off to get control back.
I see references in previous versions: PC freezes after long period of inactivity (~> 30 min)
What should I do when Ubuntu freezes?
but these don't help me.
To try to simulate the problem I set the turn off time to 1 min. The first time moving the cursor solved the problem, so I let it go for another minute. Then I pressed the escape key. The screens came back but the mouse was frozen. I tried a Ctrl-Alt-T to get a terminal, but the keyboard wasn't responding either.
Maybe I have no choice but to do a power down, but it would be nicer if I could somehow get control back but some other method.
I'm not sure if this is a suspend problem. Since it appeared only recently, I suspect it is connected to 17.04. Thanks in advance for any help.