black screen at login, but not caused by usual suspects?

allpwrfulroot · 11-02-2010, 10:31 AM

My lab's 10.04 machine will boot up to a simplistic login screen, but won't allow logging in. I can ssh into the machine just fine, and all the lab's data is fine and accessible, but I cannot sit at the machine and work. I tried purging and reinstalling x server and gdm and ubuntu-desktop to see if there was a corrupted configuration file somewhere, but no luck. (Actually, this step caused the even-more-simplistic login screen. Don't try it.)

Suggestions? I'd rather not wipe the partition and reinstall, since that would mean at least a day's worth of reinstalling software...

AlucardZero · 11-02-2010, 11:35 AM

What's the error when you try logging in?

tommcd · 11-02-2010, 02:35 PM

Take a look at this tutorial and see if it provides a solution:
http://ubuntu-tutorials.com/2010/05/...up-workaround/
What graphics card does your computer have?

allpwrfulroot · 11-02-2010, 03:17 PM

There is no error message, merely a black screen.

The graphics card is an MSI N9400GT. 512MB DDR2, nVidia GeForce logo on the box.

I'll attempt the grub modifications later today, although I don't think the graphics card has ever needed special treatment before?

AlucardZero · 11-02-2010, 04:51 PM

Check /var/log/secure and /var/log/Xorg.0.log (or similar names) for clues and errors. Can you log in as root?

Move /etc/X11/xorg.conf out of the way if it exists and restart GDM. Does that change anything?

PTrenholme · 11-02-2010, 05:27 PM

Try installing the nVidia video driver from the "encumbered" repositories if you haven't already done so. The FOSS drivers used by default sometimes have problems with both very new and very old nVidia cards.

tommcd · 11-02-2010, 05:34 PM

allpwrfulroot,
If you can not boot to a graphical desktop to install the nvidia driver for your 9400GT, you can boot to recovery mode and install it like this:

Code:

sudo apt-get install nvidia-current nvidia-settings mesa-utils
sudo nvidia-xconfig
sudo reboot

This will install the driver and related utilities, configure the driver, and reboot the system.

You may not need to use sudo in recovery mode. It has been some time since I have needed to boot to recovery mode, so I am not sure if sudo is need or not. Either way, using sudo in recovery mode will not hurt anything.

allpwrfulroot · 11-07-2010, 06:54 PM

No love. Will have to reinstall. Thanks for helping, though, I appreciate it.