Same problem.
It started when I upgraded from 13.10 to 14.04.
GF108GLM [Quadro 1000M] NVIDIA driver version: 331.38 from nvidia-331-updates Thinkpad W520
Same problem.
It started when I upgraded from 13.10 to 14.04.
GF108GLM [Quadro 1000M]
NVIDIA driver version: 331.38 from nvidia-331-updates
Thinkpad W520