Use your Mac’s internal graphics to save battery life
If you have a MacBook system that contains dual graphics cards, then you have the option of enabling either the internal graphics or the discrete graphics card, depending on the hardware demands of the tasks you are running.
Integrated or “internal” graphics functions are included on the Intel processor in your Mac (though some prior Mac systems used Nvidia chipsets with Nvidia-branded internal graphics). This graphics option is relatively slow but also draws far less power than a dedicated graphics processor. The integrated graphics are powered fully when the system is turned on.
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