Dell OptiPlex GX280 - Manual (Page 125)

14 front-panel audio cable connector (FRONTAUDIO)
Tower System Board
1 fan connector (FAN) 12 password jumper (PSWD)
2 processor connector (CPU) 13 PCI Express x16 connector (PEG)
3 power connector (12VPOWER) 14 PCI Express x1 connector (PCIE1)
4 memory module connectors (DIMM1, DIMM2, DIMM3, DIMM4) 15 PCI connector (PCI1)
5
serial ATA drive 0 and 2 connectors
(SATA0, SATA2)
16 PCI connector (PCI2)
6 front-panel connector (FRONT PANEL) 17 serial connector (SER_PS2)
7
CD drive analog audio cable connector for optional analog audio cable
(CD_IN)
18 floppy drive connector (FLOPPY)
8 power connector (POWER) 19 battery socket (BATTERY)
9 CD/DVD drive connector (IDE) 20 internal speaker (SPEAKER)
10 RTC reset jumper (RTCRST) 21 external speaker connector
(EXT_SPKR)
11 intrusion switch connector (INTRUDER)