ASUS UX21E series PowerXpress can manually change the GPU currently in use according to the system platform and graphics needs.
From the Graphics Settings tree, click PowerXpress.
Select the appropriate performance setting:
Power-saving GPU Choose an integrated GPU that consumes less power but only provides basic video and video quality.
High-Performance GPU Choose a GPU on a discrete graphics card that consumes more power but provides superior video and image quality.
Note: During the switching process, the monitor will normally be black for a period of time.
Selecting a setting will automatically switch to the appropriate GPU, and the PowerXpress Status box will update to reflect the GPU in use.