I hate many things about Ubuntu, but the most frustrating is that it doesn’t save backlight brightness settings and the screen glows right into my face at full power on each boot.
Another thing is that on one of the laptops WiFi is always off after reboot, even though the hardware switch is on and Windows doesn’t have these issues on the same machine. To solve the brightness problem use xbacklight. Install it through package manager. Now we must make it run and set desired brightness on boot. The first candidate is rc.local, but it executes before X starts, and we need to control brightness in gnome. So open gromerc and add two commands to it. The first one is to force unblock all network interfaces. The other is to force 20% backlight setting. Both commands will be executed as soon as you login to your user account.