Comment 6 for bug 1366165

I have the same problem on my work PC. Any time my monitor is put to sleep for inactivity, the video signal never returns within X. After the inactivity, I turn the monitor back on after it has shut off due to no signal, and moving the mouse/typing keys will not bring the signal back, monitor just says no signal. If I press ctrl+alt+f1 then I get a console and the monitor comes back to life. I have to restart lightdm (killing all my programs) to get back into X. dmesg only shows the following:

[4219918.274807] init: tty1 main process ended, respawning
[4219923.733629] init: Failed to spawn hybrid-gfx main process: unable to execute: No such file or directory
[4219924.646159] nvidia 0000:01:00.0: irq 49 for MSI/MSI-X