Sony PCG-TR2A - Manual (Page 51)

Playing DVDs
You can play DVDs in your computer's optical drive and view the video on a multimedia display.
Connecting a Multim edia Display
Do not remove the optical drive when the computer is in a power saving mode (Standby or Hibernate). Doing
so may cause the computer to malfunction.
Connect the external optical drive if you plan to use one.
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