I have Ubuntu 12.04 LTS 32bit in my Dell Latitude E5530 with Intel core i5 and graphics of Intel® Ivybridge Mobile x86/MMX/SSE2.
I can change Brightness with Fn buttons but screen brightness reset to maximum after every reboot. There is no Brightness control in Brightness & Lock menu.
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor"
Why isn't there the Brightness slider in menu?