Dell Precision T7400 (Late 2007) - Manual (Page 165)

Adding and Replacing Parts 165
DC Power Connector P18
DC Power Connector P19
5 +12 VC Blue/White
Pin Number Signal name 18-AWG Wire
1 12 VE Blue/Yellow
2 12 VE Blue/Yellow
3 12 VE Blue/Yellow
4 COM Black
5 COM Black
6 COM Black
Pin Number Signal name 18-AWG Wire
1 COM Black
2 12 VD Yellow/White
3 12 VD Yellow/White
4 3.3 V Orange
5 COM Black
Pin Number Signal name 18-AWG Wire
4 5 6
1 2 3
5 6 7 8
1 2 3 4