The problem occurs only with NVIDIA proprietary drivers versions 304.117 and 331.38, and Ubuntu 14.04 LTS.
A month ago, I was running Ubuntu 12.04 LTS and it worked flawlessly with NVIDIA proprietary driver. I did not take note which version it was though; I assume it was the latest since usually this is what I select. Because it was working with 12.04, the problem might not be with the driver per se, but the interaction between it and the graphical/kernel environment.
Reverted to using NVIDIA proprietary drivers because Nouveau cannot resume from sleep (year old critical issue: https:/ /bugs.launchpad .net/ubuntu/ +source/ xserver- xorg-video- nouveau/ +bug/1111884)
The problem occurs only with NVIDIA proprietary drivers versions 304.117 and 331.38, and Ubuntu 14.04 LTS.
A month ago, I was running Ubuntu 12.04 LTS and it worked flawlessly with NVIDIA proprietary driver. I did not take note which version it was though; I assume it was the latest since usually this is what I select. Because it was working with 12.04, the problem might not be with the driver per se, but the interaction between it and the graphical/kernel environment.