Ubuntu Low Resolution fix : no higher than 640×480

I recently installed Ubuntu 10.04 on an old machine I had lying around, the aim was to use it as a media PC. The machine is very very old and with Ubuntu it boots up in about 30 seconds compared to the 30 minutes windows XP used to take. I don’t know the specs of the PC, it has a pentium 4 I think, and maybe 256mb of RAM.

I had a problem trying to get the display to work on my LCD tv, an LG 32LG3000, the graphics card I was using was an Nvidia Geforce 6600, using the VGA output.  I couldn’t get the resolution above 640×480, I spent a while looking for a solution on the internet but couldn’t find one which worked. The closest I got was with Ubuntu’s wiki page, but using their ‘cvt’ or ‘gtf’ utility got me the error “could not set the configuration for crtc 58″, or something similar.

Eventually I found the right solution for me, the answer was to edit the xorg.conf file manually and add the screen resolution in there. The steps to do that are below:

1. Backup your xorg.conf file. Just in case anything goes wrong! Use this code:

sudo cp /etc/X11/xorg.conf /etc/X11/xorg.conf_backup

2. Find the modeline and the ‘horizsync’ and ‘vertrefresh’ numbers for your screen. I found mine through mythtv’s Modeline Database, but I expect a Google search will be able to find you yours if it’s not on there or in your screen’s manual.

3. Add the above info to your xorg.conf file. Use the following code to edit your xorg.conf, add the modline, ‘horizsync’ and ‘vertrefresh’ numbers under the ‘Monitor’ section:

gksudo gedit /etc/X11/xorg.conf

For example, here’s what my xorg.conf used to look like:

And here’s what it looks like now:

I also added the following line, I don’t know if it’s needed but it seems to work:

Option “Preferred mode” “1360×768″

4. Open your monitor settings and change the resolution (hopefully). Go to System -> Preferences -> Monitor. For this to work you need to use the Nvidia control panel, the options for different resolutions for your screen should now be listed, and should hopefully work.

It was a pain in the a** trying to get this to work so I hope it’s of some use to someone else! By the way, the media PC idea didn’t work out, the computer just wasn’t powerful enough, it couldn’t handle mkv files, the sound wouldn’t work properly, and the PC itself was just noisy as hell. Worst media PC ever.