On Fri, Aug 2, 2013 at 3:11 PM, Josep Lladonosa jlladono@gmail.com wrote:
"Before" means with previous kernels that worked with
GRUB_CMDLINE_LINUX="acpi_osi=Linux acpi_backlight=vendor"
That's probably a different issue. You would need to bisect the problem.
I have not checked this issue with acpi_osi="!Windows 2012".
Please do.