The Bonobo Journal

On my Averatec 2370 running the binary Nvidia drivers “Nvidia”, if I set it to go to sleep or hibernate, then wake the computer, and then logout, the screen goes from the 1280×800 to 1024×768. This problem affects both Ubuntu 7.10 and Fedora 8.

Xorg gets the screen size from reading the Extended display identification data (EDID) information from the monitor. It appears that the EDID is read correctly when you start up, but after hibernation or sleep the info gets scrambled.

To correct the problem, I copied the correct EDID info into file when the EDID info is not scrambled. I then have xorg read the file instead of reading it from the monitor.

Instructions for Ubuntu

1. Login as a user who can sudo.
2. Open a command line window.
3. Run the following command to launch the Nvidia Settings application:
   
gksudo nvidia-settings

4. Click on the “DFP-0 - (Seiko) option. This brings up the options for the LCD monitor
5. Click on the “Acquire EDID” button. This gets the EDID config info from the LCD monitor and ask where to save it. I saved it as “/etc/X11/SeikoEdid.bin”.
6. Sudo edit the /etc/X11/xorg.conf file. Add the following line to the section for “Monitor”.
   
Option “CustomEDID” “DFP-0:/etc/X11/SeikoEdid.bin”


What seems to be happening is when you start X, it reads the EDID from the monitor. After a suspend or hiberate, you can no longer read the EDID for some reason. As a result, the driver defaults to a lower resolution, causing the screen to shrink. What I am doing is to record the correct EDID information into a file when it is correct and have X read from the file instead of the device. This should work around the problem.

For Fedora 8, the instruction is similar, except that you login as root and run the Nvidia-Settings menu from the menu.