HP Compaq Presario,Presario 1700 Supplementary Manual page 26

Here's what's on the
underside of your Notebook.
This is where the memory
compartment, the battery
release switch, and the
FutureBay release switch
are located.
Tip
Before calling Compaq
Customer Support you
will need the serial number
from the underside of
your Notebook.
See also
"Using Battery Power" later
in this guide for more
information about the
Battery Release Switch.