Remember to call "sudo update-grub" after making modifications in /etc/default/grub. The update-grub script assures that /boot/grub/grub.cfg is updated with the new information. I assume you're using GRUB2.
Remember to call "sudo update-grub" after making modifications in /etc/default/grub. The update-grub script assures that /boot/grub/grub.cfg is updated with the new information. I assume you're using GRUB2.