After upgrading my desktop PC to Ubuntu 12.04 (actually my main machine) I started experimenting many Xorg crashes and instability issues. I reported the bug, but I had to find a solution or I should have rolled back to Ubuntu 11.10. The problem (from my point of view) is of the new Nvidia 295.40 binary drivers. I also tried an older version (295.33) experiencing the same problems. I then decided to give the Nouveau opensource drivers a try.

I must say that in over 24 hours I didn’t have a single Xorg crash. My desktop is very stable and Nouveau drivers are pretty fast: I can watch a 1080p video on Youtube in full screen without having any problem. The only problem with my machine is that I’m using a VGA Switcher to share my monitor wit Xbox (see this old post), so my monitor capabilities cannot be detected automatically and I had to do some manually tuning of the Xorg configuration.

First of all I had to resolve a very annoying problem: the screen was blinking every 10 seconds and this really hurted my eyes. To fix this I had to add a kernel parameter: **drm_kms_helper.poll=0
**you need to add this string in /etc/default/grub to the GRUB_CMDLINE_LINUX_DEFAULT parameter. After this your line should look like this one: GRUB_CMDLINE_LINUX_DEFAULT="quiet splash drm_kms_helper.poll=0"

Don’t forget to execute: sudo update-grub from the command line.

Then I had to create a proper xorg.conf setting my resolution (1680x1050) manually:

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Section "Monitor"  
Identifier "DVI-I-1"  
VendorName "Asus"  
ModelName "Ancor Communications Inc VW222"  
Modeline "1680x1050R" 119.00 1680 1728 1760 1840 1050 1053 1059 1080
+hsync -vsync  
Option "PreferredMode" "1680x1050R"  
EndSection

Section "Screen"  
Identifier "Screen0"  
Monitor "DVI-I-1"  
EndSection

How do you generate the Modeline line? It’s very simple. Just execute: “cvt -r 1680 1050” in the command line and you’ll get a line similar to the one I added (of course substitute those numbers with the resolution you want).

You have to save this file in /etc/X11/xorg.conf and reboot your system to use all the new settings. Now my system runs nicely and very fast! I’m really enjoying the new Ubuntu 12.04 Precise Pangolin. I just hope that Nvidia guys will fix the sta
bility issues of their driver as soon as possible, so I’ll be able to choose again between the opensource driver and the closed source one (faster with 3D stuff, but more unstable as you can see).

A big thanks to everyone in #nouveau IRC channel on Freenode. They were very kind to help me configuring their opensource driver.