Originally Posted by danix
We have been able to reproduce a difference in functionality between the 295 and 302 drivers as described in this thread (display is black after suspend/resume in 302 and is fine in 295); however, we are only able to reproduce this symptom when running with a framebuffer console. The NVIDIA driver requires that the primary display device drive a VGA text console; non-VGA consoles are not supported.
While reviewing the nvidia-bug-report.log files attached to this thread so far, we noticed that most people appeared to be using framebuffer consoles.
Originally Posted by ltmon
Switching to VT (ctrl-alt-F2) and then suspend (sudo pm-suspend) works fine, and resumes to the console.
Switching back to X (ctrl-alt-F7) is then a frozen black screen.
Restarting X before switching back (sudo restart lightdm) works fine.
I believe this was the case with or without a vesa fb.
I can confirm that the exact same behavior (black screen with backlight on after waking up from suspend, no signal on external monitor, unless on a text console and restarting x) occurs even with vga=normal, so this does not
seem to be related to a framebuffer console. Lenovo T410 with NVS3100m, Ubuntu 12.04 LTS with 302.11 driver.
As a side note: The fact that most bug reports here are using a framebuffer console probably stems from the fact that most of today's popular Linux distributions have that enabled by default. Requiring e.g. all Ubuntu users to turn off the framebuffer console manually if they want to use the accelerated graphics driver, without even a clear notice about that, sounds like a non-starter to me.