Introduction

In most GNU/Linux systems, you are provided with multiple TTYs or virtual consoles. Typically 6. These are accessed by pressing Ctrl+Alt+F1 through F6 with your XServer typically running on TTY7 or Ctrl+Alt+F7 and the console logging done to TTY8 or TTY12. (Ctrl+Alt+F8 or F12). The default resolution for these console screens is 80 columns by 25 rows. This default resolution is inconvenient for most activities done on the console. Thankfully, this is an old problem and has been solved for a long time.

The following instructions will provide you the necessary steps to increase the resolution of console screens through the use of the vga kernel option.

Warning: Be careful to not chose a resolution that is higher than what your display device supports. Doing so will require you to boot a rescue disk and adjust the vga mode to a supported value.

Increase the resolution of the virtual consoles

Chose preferred console resolution

The default size of the console is 25x80 chars using vga (640x480 pixels) for historical reasons. In order to utilize modern display resolution you will need to override this settings during the operation system boot process. Please note that widescreen format support is very limited in the VESA standards. Pick a appropriate value from the matrix below, e.g. 791 for 16 bit 1280x1024.

                320×200 640×400 640×480 800×500 800×600 896×672 1024×640        
16 colors                                       770                             
256 colors              768     769     879     771     815     874             
15-bit          781     801     784     880     787     816     875             
16-bit          782     802     785     881     788     817     876             
24-bit          783     803     786     882     789     818     877             
32-bit                  804     809     883     814     819     878             


1024×768        1152×720        1280×1024       1440×900        1600×1200
772                             774
773             869             775             864             796
790             870             793             865             797
791             871             794             866             798
792             872             795             867             799
824             873             829             868             834

A more complete description and table can be found on the Wikipedia VESA BIOS Extension article.

Edit /boot/grub/menu.lst

Append vga=791 in the end of the kernel line. Your root=UUID will look different .Do not edit this since it will cause your computer to fail booting. Please be warned.

In the kernel line below the option splash is removed since it might cause LCD monitors to entering sleep mode during the boot process when using DVI input. This is not a serious error but a very annoying side-effect from changing the console resolution. This failure might apply on other configurations as well.

title           Ubuntu 8.10, kernel 2.6.27-9-generic
uuid            636dc411-e53a-4776-a9e9-4fc9e277f445
kernel          /boot/vmlinuz-2.6.27-9-generic root=UUID=636dc411-e53a-4776-a9e9-4fc9e277f445 ro quiet splash vga=791
initrd          /boot/initrd.img-2.6.27-9-generic
quiet
  • Tip, If you would like to test the setting but not make a permanent change as above it's possible to edit grub options during computer booting. When grub is loading press ESC to enter the boot menu, chose to edit the kernel line and append vga=791. Continue to boot linux.

Set usplash resolution

To keep the Ubuntu slash logo centered, you must set the resolution to match what you chose from the table.

sudo vi /etc/usplash.conf

Change xres= to the first 1/2 of the resolution and yres= to the second 1/2. e.g.

# Usplash configuration file
xres=1024
yres=768

Rebuild the kernel image

This step is necessary to rebuild the usplash graphics in the kernel image being used upon next reboot. This step might also be necessary to perform after a kernel upgrade.

sudo update-initramfs -u

Reboot

Hopefully you should see the boot messages with a smaller font upon the boot process.

Hints

If you are interested in seeing the supported modes of your video card, you can set the vga= line to ask and reboot. vga=ask

Upon Grub loading, it will present you with a table of the supported modes of your video card. The format is X by Y by Color Depth in bits. The number to the left of the resolution is the VESA mode. You need to convert the code to Linux VGA modes. This is typically done by adding 512 to the VESA mode. This is not always the case and can be values greater or lower.

This section was assembled using information from different sources.


ConsoleFramebuffer (last edited 2009-09-21 14:30:24 by sbrown1992)