Asus R750JV - Manual (Page 21)

Notebook PC E-Manual 1
Right Side
Headphone output and S/PDIF output combo jack port (on
selected models)
This port allows you to connect your Notebook PC to amplified
speakers or headphones. You can also use this port to connect
your Notebook PC to S/PDIF (Sony/Philips Digital Interconnect
Format) compliant devices.
Microphone input combo jack port
The microphone input jack port is used to connect your
Notebook PC to an external microphone.
USB 3.0 ports
These USB (Universal Serial Bus) 3.0 ports provide a transfer rate
of up to  Gbit/s and are backward compatible to USB .0.
Optical drive
Your Notebook PC’s optical drive may support several disc
formats such as CDs, DVDs, recordable discs, or rewritable discs.
Optical drive indicator
This indicator lights up when the optical drive electronic eject
button is pressed while the Notebook PC is powered on. This
indicator also lights up when the optical drive is currently
reading data from or writing data to a disc.