Ubuntu 13.04 slowing down due to X taking 50-100% of CPU

Question

I have strange issue. I use my PC mostly to run some Java app, execute some command line, watch movies and use browser (Chromium), eg. to watch YouTube, play some Flash games and read. Not much more.

Some time ago I spotted some issue with one of the processes taking a lot of CPU and causing low frame rate (2-4FPS or similar, even though the sound is okay) until I restart my machine. The command is as follows, when viewed using htop:

/usr/bin/X :0 -background none -verbose -auth  /var/run/gdm/auth-for-gdm-EirVFF/database -nolisten tcp vt7

From https://askubuntu.com/a/179795/18697 it looks like that may have been caused by bad driver or some extra features taking too much processing speed.

From Settings->Details->Graphics I know, that the driver setup is "Intel® Sandybridge Mobile", but I have not found the ability to change that, nor I found any other settings (eg. related to Compiz). According to my PC specs, the card I have is NVidia GT520MX.

I could mess with various configuration files, try to install various external libraries, but I think there is some standard way to deal with that.

How can I fix this problem, so X stops taking so much CPU and the PC works faster?

Update:

I applied tips listed here, which came down to typing the following commands:

sudo apt-add-repository ppa:xorg-edgers/ppa
sudo apt-get update
sudo apt-get install nvidia-current nvidia-settings

But when I run sudo nvidia-settings, I see the following message:

You do not appear to be using the NVIDIA X driver. Please edit your X configuration file (just run `nvidia-xconfig` as root), and restart the X server.

The problem is, that nvidia-xconfig is not found in my system, and installing nvidia-current does not change it.

Any additional clues?

Answer 1

I think the nVidia driver you reference is a kernel module. This means you have to unload and "blacklist" nouveau (or any other such kernel video driver). The installation of the nvidia proprietary driver usually does this by making modprobe configuration entries. But unless you're very familiar with how these drivers work (as in, bind to the text console), and you can poke around in /sys to deactivate them, you'll have to reboot. That will basically "purge" nouveau and allow nvidia to take effect. Then nvidia-settings can use its proprietary protocol(s) to manipulate the nvidia kernel module.