Adding and replacing system board components 9-3The system board, sometimes called the planar or motherboard, is the main circuitboard in the system unit. It supports a variety of devices and provides other basiccomputer functions that are preinstalled or that you can install later. The systemboard shown on the previous page has the following parts:Memory module sockets (for DIMMs). Your system board has two 168-pin sockets for Dual lnline Memory Modules (DIMMs).The DIMM socketssupport 3.3V single-or double-sided Synchronous DRAM (SDRAM). Themaximum system memory is 1 GB.Power Switch connector (J15)Processor fan power connector (J2)HDD LED and Power LED connector (J18)Primary IDE connector (J4). Holds signal cables that attach to IDEchannel 1.Processor FAN, processor and heat sink (U5)Secondary IDE connector (J5). Holds signal cables that attach to IDEchannel 2.Diskette drive connector (J14)Battery (BAT1) System battery.Flash ROM BIOS (U16)PCI adapter card connector (J11 - PCI SLOT1). This is the first PCIadapter card connector.PCI adapter card connector (J12 - PCI SLOT2). This is the second PCIadapter card connector.PCI adapter card connector (J13 - PCI SLOT3). This is the thirdadapter card connector.USB and Local Area Network Connector (J7)CD-ROM audio signal connector (J19)Audio and game port connector (J20)Power supply connecter (J1)Keyboard and mouse connectors (J17)Parallel, Video and Serial connectors (J16)Digital Flat Panel connector (J6)Front USB, headset, microphone, and volume control (J25) (forconsumer desktop model only)1234567889101112131415161718192021
