Comment 22 for bug 1170911

My experiments:
0) With 12.10 everything worked perfectly.
1) 13.04, upgraded from 12.10. Since then I cannot sleep, hibernate, or shutdown my computer. After some hard resets system starts without the X-server, sometimes with.
2) Uninstalled modem-manager, no change (except no error message about that).
3) Since I changed nvidia-304-updates to nvidia-313-updates, computer was turned off properly, but only for the first time. 310-updates - same problem.
4) Clean install of 13.04 on another partition, no nvidia driver. Tried to suspend(sleep), it worked, but after wake up the screen was only blank and I had to do hard reset again.
5) Now I am on my old partition and I have no sound. It seems there is something wrong not in nvidia, but in kernel and it is somehow related to drivers (nvidia, modem, sound, hdd ...?). And it is not fully repeatable, maybe some race condition? Is / unmounted really after all unneeded applications and drivers are stopped?