Ubuntu 12.04 systems sometimes boot directly into a TTY terminal instead of the graphical desktop, displaying the Xorg error: "VESA V_BIOS address 0x0 out of range". This error typically indicates a problem with graphics drivers or incorrect Xorg configurations. Addressing this issue involves troubleshooting your graphics settings and updating or reinstalling appropriate drivers.

Method 1: Reconfigure Xorg Settings

Step 1: First, log in to the TTY terminal using your username and password. Once logged in, stop the current graphical display manager. This ensures that changes to the configuration won't conflict with running graphical processes. Execute the following command:

sudo service lightdm stop

If you're using a different display manager, replace lightdm with your display manager's name, such as gdm or sddm.

Step 2: Next, reconfigure your Xorg settings. This resets the graphical environment to default configurations, resolving many common display errors. Run:

sudo dpkg-reconfigure xserver-xorg

Follow the on-screen prompts to complete the configuration process. The utility guides you through selecting appropriate options for your hardware.

Step 3: After reconfiguration, restart your display manager to test if the graphical desktop now loads correctly:

sudo service lightdm start

If successful, you will see your graphical login screen. If the issue persists, proceed to the next method.

Method 2: Install Proprietary Graphics Drivers

Step 1: Log into your TTY terminal as previously described. The VESA error can occur due to missing or outdated graphics drivers, especially with NVIDIA or AMD graphics hardware. Installing proprietary drivers often resolves compatibility issues. First, ensure your package lists are updated:

sudo apt-get update

Step 2: Next, install the appropriate driver based on your graphics hardware. For NVIDIA graphics cards, use:

sudo apt-get install nvidia-current

For AMD graphics cards, use:

sudo apt-get install fglrx

If you're unsure about your graphics hardware, identify it using:

lspci | grep VGA

This command lists your graphics hardware details, helping you select the correct driver.

Step 3: After installing the proper driver, reboot your system to apply changes:

sudo reboot

Upon reboot, your graphical desktop environment should load without the VESA error.

Method 3: Modify GRUB Boot Parameters

Step 1: If driver installation or Xorg reconfiguration doesn't resolve the issue, modifying GRUB boot parameters can help. Log into your TTY terminal and open GRUB's configuration file in a text editor:

sudo nano /etc/default/grub

Step 2: Locate the line starting with GRUB_CMDLINE_LINUX_DEFAULT. Add the parameter nomodeset to disable kernel mode setting, which can trigger the VESA BIOS error. The edited line should look similar to:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash nomodeset"

Save the changes by pressing Ctrl + O, then exit nano by pressing Ctrl + X.

Step 3: Update GRUB to apply your changes:

sudo update-grub

Reboot your system:

sudo reboot

This adjustment often resolves boot-time graphical display issues related to hardware compatibility.

After following these steps, your Ubuntu 12.04 system should boot normally into the graphical desktop environment. Keep your system and drivers regularly updated to prevent similar issues in the future.