Sony PCG-SRX99 - Manual (Page 58)

Connecting a PC Card Bus Drive
You can use an optional optical drive, such as a Sony DVD-ROM or CD-ROM drive (PCGA-51/A), with your computer. If you
use an optional drive when your computer is running on battery power, the battery life will be shorter. The drive draws
power from the computer through a PC Card.
If you connect a non-Sony DVD drive to your VAIO ® computer, the DVD playback may not function
properly. The bundled DVD software must be installed to play a DVD.
For best performance, it is recommended that you use a Sony compatible DVD drive.
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