Dell Vostro 3550 (Early 2011) - Manual (Page 100)

USB Storage Device Specify which USB storage device the
computer can boot through.
CD/DVD ROM Drives Specify which CD/DVD the computer can
boot through.
eSATA Specify which eSATA device the computer
can boot through.
Network Specify which network device the
computer can boot through.
Exit
This section allows you to save, discard, and load default settings before exiting
from System Setup.
100