HP Compaq NX9600 Hardware And Software Manual page 131

Drives
All models have a digital drive bay that can be used with an
optional HP USB Digital Drive. For more information, see the
"HP USB Digital Drive (Select Models Only)"
this chapter.
An optional external drive can be added to the system by
connecting it to one of the USB (Universal Serial Bus) or
1394 ports on the notebook.
Additional data storage can be added with digital cards including
SD Memory Cards, MultiMediaCards, Smart Media, xD-Picture
Card, Memory Sticks, and Memory Stick Pro. For more
information, refer to
7–2
"Using Digital Cards,"
section, later in
in Chapter 6.
Hardware and Software Guide