Every time I boot up Ubuntu or Mint, after choosing an OS from GRUB menu, before logging in, screen brightness is set to 0. What is the reason behind that?
I always end up manually turning on the brightness in order to see the logo and then login screen. It does not happen in other distros like Debian. I encounter this in Ubuntu 12.04, 13.10, Mint 15 and Mint 16.
computer specs: Laptop Lenovo g500; intel celeron 1005M 1.9G; RAM 4GB; integrated graphics; win8/mint16 dualboot
echo 5 >/sys/class/backlight/acpi_video0/brightness
in a case like this one or you may have for some reason an inappropriate acpi setting passed to a bootloader like grub in a case like that maybe. You should also include in your question the brand of your graphics card and/or computer and specify if it's a laptop, as there's also the question of the specific driver if it's not simply configuration.