Dell OptiPlex 755 User Manual page 170

12. Replace the floppy drive or media card reader (see
13. Replace the optical drive (see
14. Replace the computer cover (see
15. Connect the AC power cable to the power supply AC power connector.
NOTICE: To connect a network cable, plug the cable into the network wall jack and then plug it into the computer.
16. Connect your computer and devices to electrical outlets, and turn them on.
DC Power Connectors
NOTE: The power supply installed in your computer is one of two options as illustrated below.
DC Power Connector P1
Pin Number Signal Name
1 +3.3 VDC
2 +3.3 VDC
3 GND
4 VCC (+5 V)
5 GND
6 VCC (+5 V)
7 GND
8 PS_PWRGOOD*
9 P5AUX
10 V_12P0_DIG
11 V_12P0_DIG
12 +3.3 V
13 +3.3V
(optional)
14 -12 V*
15 GND
16 PWR_PS_ON
17 GND
Installing a Floppy
Installing an Optical Drive).
Replacing the Computer Cover).
18-AWG Wire
Orange
Orange
Black
Red
Black
Red
Black
Gray
Purple
Yellow
Yellow
Orange
Orange
Blue
Black
Green
Black
Drive).