Sony PCG-GRX690P - Manual (Page 143)

Using Computer Monitors and Projectors
143
Disconnecting a computer monitor or projector
You can disconnect the external computer monitor or projector by unplugging the
display or Monitor (VGA) cable from your computer’s port. Disconnecting the
external display when the computer is in a power saving mode (Standby or
Hibernate) may cause the computer to malfunction.