Fix: Laptop Screen Backlight Brightness Reset on Every Startup/Restart
The resetting of laptop screen backlight brightness on every startup/restart has been a common problem on my Asus N53SV and HP mini 210, both are gear up with elementary OS. Same thing happen as well after laptop come out of sleep mode which is annoying I have to adjust the screen brightness again. To get the screen brightness right, here is a solution:
Type sudo nano /etc/default/grub
Find GRUB_CMDLINE_LINUX_DEFAULT="quiet splash". Replace the whole line with GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor" as screenshot below.
Press ctrl + o to WriteOut/Save and press ctrl + x to Exit.