HP xw4550 Service And Technical Reference Manual page 152

AUX_IN (auxiliary audio)
Internal USB system board 2x5 connector
The 2x5 internal USB system board connector can be mated to
either a wide 2x5 option cable connector or a narrow 1x5 option
CAUTION:
Always key all option connectors to the blank pin 9 position to
prevent damage to connectors and equipment. Always connect a
narrow 1x5 option cable connector to pins 1,3,5, and 7 only.
System fan (rear chassis), processor fan, and PCI fan (front
chassis) system board connectors
144 Appendix A Appendix A—Workstation connector pins
cable connector.
Possible equipment damage.
Pin Signal
1 AUX_LEFT
2 AGND
3 AGND
4 AUX_RIGHT
Pin Signal
1 +5V
2 +5V
3 USB6#
4 USB7#
5
USB6
6
USB7
7
GND
8
GND
9
(pin not keyed)
10
(not connected)
Pin Signal
1 Ground
2 +12V
3 Tach
4 CMD
ENWW