Recover From Crashed X Window Session - Ubuntu TipsnTricks

Since having google start to spy on the website I’ve noticed a trend with viewers. I’m going to assume that the #2 spot of firefox users on Windows are people who’ve hosed their systems in some manner and are looking for help.

First tip with X-Windows or X for short is to remember to make a backup of your original /etc/X11/xorg.conf file.

sudo cp /etc/X11/xorg.conf /etc/X11/xorg.conf.orig.bak

That way if there is any time that you end up at the command prompt and cant get X up you dont have to reboot into Windows or jump on the other machine to see what went wrong.

Once you have copied the original back to /etc/X11/xorg.conf issue the following commands to restart X.

sudo /etc/init.d/gdm restart

or for KDE users

sudo /etc/init.d/kdm restart

You should see a bit of flashing screen and then be welcomed back by a graphical login prompt!

What if that does not work?

Lets consider you just added a new video card.

If the first was a ATI card and the new one is a Nvidia card you have to do two things.

ATI cards typically use the Driver “radeon” setting in the xorg.conf file under Section “Device”. You will have to edit the file.

After backing up your original of course!

sudo vi /etc/X11/xorg.conf

hit the backslash / key

type in the string you wish to find in this case radeon and hit enter

you should get to a uncommented line that looks like this

Driver “Radeon”

hit escape move to the R in radeon and hit the x key until radeon is gone and you have “” left.

hit the right key to put the cursor under the second ” and then type i for insert then type in nv so it looks like

Driver “nv”

once that’s done hit escape again. then type a colon : and then type wq for write quit.

If you screw up just type q! after hitting escape and then colon to quit without saving. Vi is a bit scary at first but recovery is easy if you remember to save a copy before and also to save only when satisified with your changes. q! will be your best friend!

Once that’s done follow the above instructions for restarting GDM or KDM and hopefully you’ll be greeted with your X login screen again.

If you’re going the other way from Nvidia to ATI (I really pity you since driver support is still pretty crappy) just reverse the driver strings.