Ubuntu – ‘PRIME Profiles’ tab missing in NVIDIA X Server Settings (Ubuntu 16.04)

I have nvidia-settings and nvidia-prime installed, but the 'PRIME Profiles' tab is missing.

How can I fix it to be able to switch between my GPUs?

Update:

~$ lspci -k | grep -EA2 'VGA|3D'
00:02.0 VGA compatible controller: Intel Corporation 4th Gen Core Processor Integrated Graphics Controller (rev 06)
    Subsystem: Hewlett-Packard Company 4th Gen Core Processor Integrated Graphics Controller
    Kernel driver in use: i915
--
01:00.0 3D controller: NVIDIA Corporation GK208M [GeForce GT 740M] (rev a1)
    Subsystem: Hewlett-Packard Company GK208M [GeForce GT 740M]
    Kernel driver in use: nouveau