Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have an Ubuntu 9.04 PC with an nVidia graphics system running at 1920x1080 outputting through an HDMI port. This all works fine until I enable the visual effects from the System > Preferences > Appearance... dialog. Then, the screen update freezes and the screen updates, when they happen, tend to contain bits of other windows / corruption. The system is still running, albeit very sluggishly, so I can switch the effect off. I'm using the restricted nVidia drivers (there may be a newer driver, but I've tried a few versions and they all exhibit the same problem).

Any ideas what's going on and how to fix it?



From what I remember (the PC is at home, I'm writing this at the office), it's using this motherboard which has an nVidia GeForce 9400 on it.

share|improve this question
up vote 1 down vote accepted

I think I have managed to fix this. First of all, I uninstalled the video driver using:

sudo sh NVIDIA.... --uninstall

where "NVIDIA...." is the video driver file. I'm writing this from memory so the argument might be wrong, it is in the readme how to do it. Then, after reading a few forums about this issue, I unsintalled all the nvidia components using:

sudo apt-get remove "nvidia*"

Then I installed the new driver, restarted, and so far it appears to be working OK.

Also, to help install the driver, I modified run level 5 to disable GDM and used the 'telinit' command to change the run level.


share|improve this answer

You might want to try a different video driver if you can, because it sounds like the current one your using is not working correctly. Which nvidia card does that computer use? I assume if your computer has a hdmi port, you probaly at least have a halfway decent video chipset, just need to find working drivers. I had a laptop once that would just crash/freeze if I attempted to turn on visual effects and things like berl. I think it was just too old though and no driver update could help it.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.