Samsung NP900X4C Ubuntu 14.04

First I turned off Secure boot and UEFI, so it wouldn't brick my laptop, but that should be fixed in latest kernels. Installed Ubuntu 14.04 64bit. Almost everything works.

1) Fn-keys
Get the Fn-keys to work:

sudo apt-add-repository ppa:voria/ppa
sudo apt-get update
sudo apt-get install samsung-tools xbindkeys-config

Then I run:

samsung-tools-preferences

 2) My USB 3.0 ports didn't work. So I fixed it by editing /etc/default/grub

sudo gedit /etc/default/grub

Change line

GRUB_CMD_LINUX_DEFAULT="quiet splash i915.i915_enable_rc6=1 i915.i915_enable_fbc=1

i915.lvds_downclock=1 pciehp.pciehp_force=1samsung-tools-preferences

pciehp command makes usb ports work, and i915 stuff downclocks the graphics so it would take less energy.

3) Brightness - On startup brightness is full, and is so brighter than sun. I fixed it by installing a program and running a command on startup.

sudo apt-get install xbacklight

Run Startup Applications and create new application:

Name: Brightness

Command: xbacklight -set 25

4) Tweaks for SSD:
Swappiness:

sudo gedit /etc/sysctl.conf

Added line:

vm.swappiness=0

Ramdisk:

sudo gedit /etc/fstab

Added line:

none /tmp tmpfs defaults 0 0

Disk scheduler:

sudo gedit /etc/rc.local

Added line:

echo deadline >/sys/block/sda/queue/scheduler

 
5) Battery life extender - So the laptop would only charge to 80% battery and save battery by doing that.

sudo gedit /etc/rc.local

Added line:

echo 1 > /sys/devices/platform/samsung/battery_life_extender