[ubuntu] Monitor Brightness Issue

Hi, I have a Lenovo Y50-70 laptop. Upon install of ubuntu (dual boot with windows 10), the monitor brightness settings were working great and responded to the hotkeys on the keyboard.

I tried and failed to update the video card drivers to the NVIDIA drivers, so I went back to the Nouveau generic drivers. Since restoring to the Nouveau drivers, my monitor brightness seems to be stuck at full.

I've tried a few solutions and here is the relevant output for most of those:

$ cat /sys/class/backlight/ideapad/brightness 
7


$ cat /sys/class/backlight/ideapad/max_brightness 
16

Here is the relevant part of my grub file:

GRUB_DEFAULT=0
#GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true
GRUB_TIMEOUT=10
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="nouveau.modeset=0 quiet splash nomodeset pcie_aspm=force acpi_backlight=vendor"
GRUB_CMDLINE_LINUX=""
# GRUB_CMDLINE_LINUX="acpi_backlight=vendor acpi_osi=Linux resume=/dev/sda7"

I also tried installing ppa:indicator-brightness, and the indicator seems to work, but the monitor does not respond to any level I set it at.

How can I get the monitor brightness to respond?