This is a bug which has been affecting me since Ubuntu 7.10 (its the first release I started with), and has happened in every single Ubuntu release since then. I have been putting off writing this bug report, because I am not sure how I can explain the problem well enough.
The issue is with the monitor I use with Ubuntu. Its a Advent F159 15inch (4:3) monitor (http://www.amazon.co.uk/Advent-F159-Silver-LCD-Monitor/dp/B000GRU6O2)
It supports 800x600 and 1024x768 with 60hz. When I boot off the live CD with Ubuntu, when the it gets to the stage with xorg takes over, it chooses the wrong setting for the monitor, the monitor says "Out of Range". What I have to do is start the Ubuntu live CD, tell it to boot into live cd mode, then unplug the vga port on monitor. After about 5mins (enough time for Ubuntu to boot), I plug in the monitor and I can see the Ubuntu desktop. It will be running on 800x600 at 60hz, 16bit.
Here, I am able to install Ubuntu. Once install is complete, and I boot into Ubuntu for the first time, the problem will happen again if I leave the monitor plugged in. So I have force a restart and unplug the monitor, boot into Ubuntu, and plug the monitor back in. Ubuntu will again set the monitor to 800x600 at 60hz, 16bit. I will then configure xorg.conf file. All I do is tell it to use 1024x768 @ 60hz, on 24bit. I restart Ubuntu, and its running at the correct resolution for me. I can now leave the monitor plugged in and it will not give me the "out of range" message.
In the time I have had Ubuntu, I have used 3 computers with this monitor. First Ubuntu PC used an ATi Radeon 7000 card (using ati open source driver), my next computer used a Intel i815 (using intel opensource driver) and my latest computer is using nVidia ION (using nvidia's drivers). This out of range problem happened with all these computers. I attach my xorg configure for all these computers.
Date: Sun Feb 28 09:38:58 2010
DistroRelease: Ubuntu 9.10
InstallationMedia: Ubuntu 9.10 "Karmic Koala" - Release i386 (20091028.5)
Bus 002 Device 003: ID 05e3:1205 Genesys Logic, Inc. Afilias Optical Mouse H3003
Bus 002 Device 002: ID 04f3:0103 Elan Microelectronics Corp.
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 004: ID 059f:0c41 LaCie, Ltd
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: Acer Aspire R3600
Package: xserver-xorg-core 2:1.6.4-2ubuntu4.1
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.31-19-generic root=UUID=121a561f-c5ef-411e-a726-1ac13fe0dd9c ro quiet splash
PATH=(custom, no user)
ProcVersionSignature: Ubuntu 2.6.31-19.56-generic
Uname: Linux 2.6.31-19-generic i686
dmi.bios.vendor: American Megatrends Inc.
dmi.board.asset.tag: To Be Filled By O.E.M.
dmi.product.name: Aspire R3600
fglrx: Not loaded
architecture: i686kernel: 2.6.31-19-generic