Greetings, I have to preface this because so many like to hate on it just to hate on it...but I am _not_ trying to start a fight. Just point in a potentially helpful direction. It has it's pros and it has its pains. With that said, take a look at your journald logs. Crank up the verbosity and take note of what is there before putting the laptop to sleep / closing the lid / hibernate / whatever. 100% of the time, without fail, every single problem I've had with my Ubuntu 16.04 laptop and my SL7.4 laptop not sleeping, waking, or crashing when I close the lid has gone back to systemd doing something it shouldn't. The vast majority of the old ways of fixing these problems don't work, you *must* fix it the systemd way. I've fixed almost* all of my issues. It is a new tougher-challenge road for me, but it's the one I'm on. :-) * The only one remaining is that I can manually lock the screen and wake the laptop up just fine. However, if I have an external monitor plugged int and I manually lock the screen for some weird reason systemd puts the laptop to sleep and won't wake up unless I open/close the lid. YET! If I just let the screensaver timeout hit, it works perfectly. That one has stumped me for the last couple of months. *shrug* If you can figure out what systemd trigger is being tripped, you can either disable that from running or potentially tweak it to work for you. Unfortunately, I don't have good resources for you. Of all the times I've asked the systemd IRC/mailing list, I have yet to get help that didn't blame me or my hardware (even when I've proved it's neither). The Ubuntu systemd group has helped several times and having a proper Up Stream Vendor license that I can install on a spare drive, boot the laptop, and use their support has helped me with several issues that I was able to take back to SL7.4 (or wait for the patch to filter down). It's primarily just been a ton of digging around on the Internet and in the log files. Good luck! ~Stack~ On 10/26/2017 09:23 AM, Stefano Vergani wrote: > Hi all, > > > I have just upgraded Scientific Linux to version 7.4 and I have found an > issue I cannot fix. Anytime I lock my PC (ThinkPad Lenovo T440p) > pressing the lock icon or simply I close the PC without locking it or > shutting it down, I am not able anymore to return in my session. The > screen remains black and I have to press the on/off button for some > seconds until it reboots. > > How can I fix this? Anyone else with the same issue? > > > thanks, > > Stefano > > > p.s. before this upgrade everything worked just fine >