nVidia GTX 870M not detected

[m654321]

Running the lspci command again, apparently shows NVidia being detected this time (see blue font below), though appears to be given an alternative labelling,
i.e. GK104M. My questions are:
1) How can I then run the laptop in NVidia rather than Intel graphics mode, given that Intel mode is the default one for this laptop?
2) How do I know if I am running in NVidia mode (or not)?

mike@mike-G750JS:~$ lspci -nn | grep '\[03'
00:02.0 VGA compatible controller [0300]: Intel Corporation 4th Gen Core Processor Integrated Graphics Controller [8086:0416] (rev 06)
01:00.0 3D controller [0302]: NVIDIA Corporation GK104M [GeForce GTX 870M] [10de:1199] (rev ff)
mike@mike-G750JS:~$