I understand that you want to disable the Nvidia card.
The Nvidia switchable graphics system is a dynamics switchable graphics system meaning it determines which graphics card to use based on the requirements of the programs running. It should use the Intel card most of the time and reserve the Nvidia card for more demanding programs. Outside of assigning specific cards to programs in the Nvidia Control Panel, there isn't a way to disable the Nvidia card permanently. It should run warmer with the Nvidia card, but it shouldn't be to the point that it would damage the other components.
