sudo apt-get install git
# type password
git clone http://github.com/mkottman/acpi_call.git
cd acpi_call
make
sudo insmod acpi_call.ko
# Download the script
wget http://lists.launchpad.net/hybrid-graphics-linux/sh3hFub0KkvH.sh
mv sh3hFub0KkvH.sh dellL702X.sh
chmod +x dellL702X.sh
# Try to switch the card off
./dellL702X.sh off
# Try to switch the card back on
./dellL702X.sh on