Dell Dimension E521 - Manual (Page 61)

Power Supply DC Connector Pin Assignments
DC Power Connector P1
1 fan connector
(FAN_CPU1) 2 processor socket (CPU) 3 memory module connectors
(DIMM_1, DIMM_2, DIMM_3,
DIMM_4)
4 power connector
(PW_12V_A1) 5 serial ATA drive
connectors (SATA2,
SATA3) 6 serial ATA drive connectors
(SATA0, SATA1)
7 front-panel
connector
(FRONTPANEL) 8 power connector
(POWER1) 9 line-in, line-out, microphone, side
surround, center, and LFE
connectors (AUDIO_6_STACK)
10 USB connectors (2)
(USB2_BACK1)
11 network connector and
USB connectors (2)
(NIC_USB1)
12 real-time clock reset jumper
(RTCRST)
13 video connector
(VIDEO1)
14 battery socket (BT1) 15 Internal USB connector (USB1)
16 PCI Express x16
connector (SLOT1)
17 standby power indicator
(AUX_PWR_LED)
18 PCI Express x1 connector
(SLOT2)
19 PCI connector
(SLOT3)
20 PCI connector (SLOT4) 21 password jumper (PSWD)
22 floppy drive
connector
(FLOPPY1)
Pin Number Signal name 18-AWG Wire
1 +3.3 VDC Orange
2 +3.3 VDC Orange
3 GND Black
4 +5 VDC Red
5 GND Black
6 +5 VDC Red