Console Framebuffer in Ubuntu

Posted by admin on December 25, 2007 under Tech Tips | Be the First to Comment

The Linux console framebuffer allows you to achieve higher screen resolutions within your Linux console. However, as of this writing, Ubuntu 7.10 Gutsy by default does not load the required kernel modules. By passing the “vga=XXX” kernel option without these modules loaded, you are left with a blinking cursor in the upper-left hand corner of your screen. Here’s how to get the console framebuffer in working order.

1. Ensure the initrd image includes framebuffer support by adding “fbcon” and “vesafb” to /etc/initramfs-tools/modules.

$ echo "vesafb" | sudo tee -a /etc/initramfs-tools/modules
$ echo "fbcon" | sudo tee -a /etc/initramfs-tools/modules

2. Remove (or comment out) “vesafb” from blacklisted modules in /etc/modprobe.d/blacklist-framebuffer.

#blacklist vesafb

3. Add the desired framebuffer variable to the default kernel options section in /boot/grub/menu.lst. For 1024×768, the string should look like the following.

#defoptions=quiet splash vga=791

4. Update GRUB.

$ sudo update-grub

5. If Usplash is configured for a higher resolution than your framebuffer, it will appear off-centered. So adjust /etc/usplash.conf to use the same resolution.

xres=1024
yres=768

6. Update initramfs to rebuild the initrd image.

$ sudo update-initramfs -u

After rebooting, your usplash will appear as normal and you can Ctrl+Alt+F1 to a console after your X environment has finished loading. The text in your console should now appear much smaller and will be much easier to use for large amounts of console work.