Dell Precision T5400 (Late 2007) - Manual (Page 164)

164 Adding and Replacing Parts
I/O-Panel Components
1 USB ports 2 diagnostic, hard-drive access, and
network integrity lights
3 headphone connector 4 microphone connector
5 front-panel thermal diode connector
NOTE: The front-panel thermal diode
cable must be installed in this
connector at all times while your
computer is running or thermal
problems may result.
2
3
4
1
5