Comment 25 for bug 240916

I have been hit by the "monitor not detected" problem too, and at several times. With an old Targa monitor, but also with some laptop LCD's. I think the problem is very common, but is often mis-diagnosed as a "driver issue".
Since the introduction of a new x-system in Ubuntu 9.x the problems has become a virtual show-stopper. In the past Ubuntu had a tool to manually select a monitor that solved the problem. Now users are simply stuck with the default resolution of 800x600 which is quite unacceptable, especially on a laptop LCD that can do 1024x768.

Ubuntu 9.x seems to work on the principle that it is always possible to auto-detect the capabilities of the Monitor, which is simply a fallacy!

There are many reasons why the plug-and-play (auto-detect) mechanism for auto-detecting the monitor capabilities is simply not present or working. For example older monitors from the pre- PnP era, or monitors connected through the VGA port with a VGA to RGB cable (older trinitron monitors, with RGB RCA video connectors), or LCD's built into older laptop where the PnP mechanism isn't implemented, ("because the display capabilities are fixed") all simply do not support the serial EEPROM with PnP monitor data. Or sometimes even if the monitor has these capabilities its not working for example because of a bad VGA cable that doesn't have (or it has but its broken) the wires for the serial EEPROM with the monitor capabilities.
In any of these cases a non-technical user , (one that is lost when told to edit the xorg.conf file) is simply confined to 800x600, even if the video hardware and monitor combo can do much higher resolutions.
A capability to manually select a monitor is essential, and should be provided.