Monitor Screen Keeps Shaking

Tommy Trussell tommy.trussell at
Thu Sep 8 13:50:58 UTC 2005

On 9/7/05, Soo-Hyun Choi <shchoi at> wrote:
> Firstly, thanks for your reply. I use the screen setup like 1280x1024
> with 60Hz under WinXP, and set the same resolution with 75Hz under
> Ubuntu. But it is still wiggling and trembling. The following is part
> of my xorg.conf file. Do you find any oddity here?
> Thank you.
> ---------- <part of xorg.conf file> ----------
> Section "Monitor"
>         Identifier      "Philips 170S"
>         HorizSync       30-82
>         VertRefresh     56-76
>         Option          "DPMS"
> EndSection

I found several web sites that say the recommended specs on that
monitor are 1280 x 1024 @ 60 Hz, and it looks to me like you have
confirmed that. I'm not certain of the BEST way to set the refresh
rate -- one way would be to back up your xorg.conf file and change the
VertRefresh number to 60Hz and see what happens, but it might be
better to collect all of the information you can about your monitor
and video card and run this command in a terminal window:

sudo dpkg-reconfigure xserver-xorg

This will take you through a detailed configuration of the video
system and generate a new version of your xorg.conf file. When you get
to the part about the monitor characteristics, you can enter whatever
the manufacturer recommends in the specs OR just the preferred
characteristics -- your 1280x1024 at 60Hz will imply several other
specific numbers, and if you're lucky that video mode will be spelled
out exactly in your documentation.

Hope that helps!

More information about the ubuntu-users mailing list