After setting up a fresh Ubuntu 14.04 on a Lenovo W540 I sometimes experience standby problems.
About 50% of the time standby works fine. I close the lid or click standby on the menu and it goes to sleep and wakes up correctly.
Sometimes though, the monitors blank, the fan goes up and it just stays that way. I found no way to revive it short of switching it off and back on.
I guess it has something to do with an application I'm running, but I couldn't figure out which one.
Is there a way to find out what went wrong with a standby?
I disabled the NVidia graphics in grub and only use the internal one.
When I ran Ubuntu 13.10 with kind of the same setup for a couple weeks on that machine I didn't experience these problems.
Thanks for any ideas!