I was able to switch the Nvidia card off manually, by using these commands which were present in the old prime-switch script (from nvidia-prime pre 0.6):
/sbin/initctl emit nvidia-off /sbin/rmmod nvidia echo "OFF" | sudo tee /proc/acpi/bbswitch
$ cat /proc/acpi/bbswitch 0000:01:00.0 OFF
I was able to switch the Nvidia card off manually, by using these commands which were present in the old prime-switch script (from nvidia-prime pre 0.6):
/sbin/initctl emit nvidia-off
/sbin/rmmod nvidia
echo "OFF" | sudo tee /proc/acpi/bbswitch
$ cat /proc/acpi/bbswitch
0000:01:00.0 OFF