Ubuntu: nforce2 smbus error at startup

sudo gedit /etc/default/grub

replace:

GRUB_CMDLINE_LINUX=""

by:

GRUB_CMDLINE_LINUX="acpi_enforce_resources=no"

mettre à jour GRUB:

sudo update-grub

Ubuntu: I/O error, dev sr0, sector 12054896

The following message is logged when closing the DVD with a medium inside:

"I/O error, dev sr0, sector 12054896" 

To see the 20 latest log messages run this command in a terminal:

dmesg | tail -n 20

To solve it, you may need to install regioset to set the DVD region code to its expected value.

Ubuntu: amd64_edac error message

message (grep edac /var/log/messages):  amd64_edac: probe of 0000:00:18.2 failed with error -22

Solution: in BIOS enable ECC monitoring

Ubuntu: convert several FLV videos to AVI/x264/mp3

for i in *.flv; do ffmpeg -ss 0 -t 5 -i "$i" -qmin 15 -qmax 25 -vcodec libx264 -acodec libmp3lame "${i%flv}avi"; done

Ubuntu <10.04: performance video

Video may freeze every few seconds due to Compiz and Graphics parameters:

STEPS: Compiz Configuration
1. Download CompizConfig Settings Manager from Ubuntu repository.
2. Navigate to.. System –> Prefences –> CompizConfig Settings Manager
3. Navigate to.. General –> General Options
4. Click “General Options” to open window
5. Click “Display Settings” tab
6. Uncheck “Detect Refresh Rate”
7. Move “Refresh Rate” slider to 60, or set 60 in the box
8. Check “Sync to VBlank”
9. Click back button to move back to main CompizConfig window
10. Navigate to.. Utility –> Video Playback
11. Uncheck “Video Playback” then exit the CompizConfig Settings Manager.

STEPS: Nvidia Configuration
1. Pull up nvidia-settings
.. Navigate to.. Applications –> System Tools –> nvidia-settings
.. or open a terminal, type “nvidia-settings” , press enter
2. Click “X Server XVideo Settings”
3. Check “Sync to VBlank” _IF_ not checked
4. Click “OpenGL Settings”
5. Uncheck “Sync to VBlank” _IF_ checked
6. click quit button
7. click quit button
8. Reopen nvidia-settings to verify that config changes were saved.
.. IF they were saved, you are done with step 8.
.. IF they were not saved, ~/.nvidia-settings-rc in your home directory
.. may be under root permissions. You will need to chown chgrp for the file.
.. Then you will need to start back at Step 1 and repeat all steps.

IMPORTANT: Reboot your machine when finished. The driver changes won’t function correctly until you reboot

From: http://www.econowics.com/linux/326/video-playback-freeze-every-few-seconds-minutes-on-ubuntu/

Ubuntu: convert many image files

From EPS to PNG:

for img in `ls *.eps`; do convert $img $img.png; done