Jimmy's Blog

I experiencing random screen distortion & flicker after upgrading to Ubuntu 10.04, I’m using Acer Notebook.
After searching in internet, there’s many forum thread & bug report discuss about this but mostly they have different hardware.
Finally I tried this method and no flickering so far.

What I do is I change my grub configuration, adding kernel parameter “i915.powersave=0”.

For Linux expert probably this is not an issue, so I dedicate this step for the newbies like

1. What I do is I modify the grub configuration which is located on /boot/grub/grub.cfg (backup before you edit it)
2. Because the access right is set to read only, let’s change it so the owner can modify it.
   > sudo chmod -c u+w /boot/grub/grub.cfg
3. Use vi or your other prefered editor to edit it.
   > sudo vim /boot/grub/grub.cfg
4. Locate the menuentry of your Linux. Example:
   menuentry ‘Ubuntu, with Linux 2.6.32-22-generic’ –class ubuntu –class gnu-linux –class gnu –class os {
   recordfail
   insmod ext2
   set root=’(hd0,4)’
   search –no-floppy –fs-uuid –set xxx-xxx-xxx
   linux /vmlinuz-2.6.32-22-generic root=UUID=xx-xx-xxx-x-xx ro quiet splash
   initrd /initrd.img-2.6.32-22-generic
   }
5. Add “i915.powersave=0” to the linux kernel line as parameter. It will become:
   menuentry ‘Ubuntu, with Linux 2.6.32-22-generic’ –class ubuntu –class gnu-linux –class gnu –class os {
   recordfail
   insmod ext2
   set root=’(hd0,4)’
   search –no-floppy –fs-uuid –set xxx-xxx-xxx
   linux /vmlinuz-2.6.32-22-generic root=UUID=xx-xx-xxx-x-xx ro i915.powersave=0 quiet splash
   initrd /initrd.img-2.6.32-22-generic
   }
6. Save & restart to check if you still experiencing screen flicker

That’s it
Hope it can work on other Notebook/PC

*Additional tips from tipster2010:

Thanks for this tip. It will work but after some time, flickering returns. I think I know the reason why:
1. Remember to turn off all screen saver and any power saving feature of your laptop after you did this.
2. Any time you change the theme of your desktop, the screensaver and power saving feature sometimes go back to default so you may need to manually change them again.