When a computer is using NVIDIA Optimus technology and the integrated GPU is being used for a particular workload, the dedicated NVIDIA GPU is not connected to the display. Instead, the integrated GPU is used to handle the graphics processing for the display, and the dedicated NVIDIA GPU is idle. This allows the computer to conserve power and extend battery life when the dedicated NVIDIA GPU is not needed.
When a workload requires the use of the dedicated NVIDIA GPU, the system will automatically switch to using the NVIDIA GPU for graphics processing, and the integrated GPU will be idle. This allows the computer to access the extra performance of the NVIDIA GPU when it is needed, while still being able to switch back to the integrated GPU when the workload is not as demanding.
Overall, the use of NVIDIA Optimus technology allows a computer to automatically and dynamically switch between the two graphics processors depending on the workload, in order to optimize performance and power usage.