Dell OptiPlex GX280 - Manual (Page 122)

2 power connector (POWER) 15 line-in, line-out, and microphone connectors
(AUDIO)
3 floppy drive connector (DSKT) 16 network connector (NIC) and USB connector
(USB2)
4 battery socket (BATTERY) 17 USB connectors (USB1)
5 internal speaker (SPEAKER) 18 diagnostic lights (DIAG LED)
6 front-panel connector (FRONT PANEL) 19 serial port connector (SER1) and video
connector (VGA)
7 CD/DVD drive connector (IDE) 20 parallel port connector (PAR)
8 serial ATA drive 0 connector (SATA0) 21 power connector (12VPOWER)
9 standby power light (AUX_PWR) 22 processor connector (CPU)
10 memory module connectors (DIMM1, DIMM2, DIMM3, DIMM4) 23 heat-sink/blower retention pad
11 PCI Express x16 connector (PEG) 24 fan connector (FAN)
12 PCI riser connector (PCI2) 25 serial port 2 connector (SER_PS2)
13 CD drive analog audio cable connector for optional analog audio
cable (CD_IN)
26 password jumper (PSWD)
Desktop System Board