I'm having an issue with Ubuntu Gnome 15.10 (also had the same issue with 15.04 before making a clean install of 15.10).
When closing the laptop lid, the computer shuts down instead of suspending. EDIT: It seems to suspend properly, but shuts down when trying to resume.
The tweak-tool settings are set to suspend whether power is connected or not.
I'm not sure what relevant information to provide, but I'm using a "Lenovo Flex 2" with nvidia graphics card drivers, no external monitors connected. (I've read about similar problems with external monitors)
Any help would be appreciated, thank you.
systemctl suspend
does the computer suspend properly? – Charles Green Dec 27 '15 at 17:41