IBM Aptiva Series Handbook page 103

The system board, sometimes called the planar or motherboard, is the main circuit board in the system unit. It supports a
variety of devices and provides other basic computer functions that are preinstalled or that you can install later. The system
board shown on the preceding page has the following parts:
Power supply connector. Holds the power cables
from the power supply.
CPU voltage regulators. Convert the system
operating voltage to match the CPU voltage.
Pentium II CPU slot. The processor is plugged into
this socket.
Battery. The system uses a 3V lithium battery
(CR2032).
Memory module sockets (for DIMMs). Your
system board has three 168-pin sockets labeled DIMM1
to DIMM3 for Dual Inline Memory Modules (DIMMs). The
DIMM sockets support 3.3V single- or double-sided
Synchronous DRAM (SDRAM). The maximum system
memory is 384 MB.
Primary IDE connector. Holds signal cables that
attach to IDE channel 1.
Secondary IDE connector. Holds signal cables
that attach to IDE channel 2.
Modem wakeup connector. This connector holds
the cable for the modem wakeup feature.
Diskette drive connector. Holds the signal cable
from the diskette drive.
Flash ROM BIOS. A 256KB Flash ROM stores the
system BIOS.
ISA adapter card connectors. The system board
includes two ISA adapter card connectors. Note that the
connector labeled ISA1 is shared with the PCI connector
labeled PCI4. You may not install an adapter card into the
ISA1 connector unless the PCI4 connector is empty.
PCI adapter card connector (PCI1). This is the
first PCI adapter card connector.
PCI adapter card connector (PCI2). This is the
second PCI adapter card connector.
PCI adapter card connector (PCI3). This is the
third PCI adapter card connector.
PCI adapter card connector (PCI4). This is the
fourth PCI adapter card connector. Note that this PCI
connector is shared with the connector labeled ISA1. You
may not install an adapter card into the PCI4 connector
unless the ISA1 connector is empty.
CD-ROM audio signal connector. Connects the
signal cable from the CD-ROM drive.
Fax/modem ring-in connector. Holds the audio
signal cable that connects to the modem card.
ATI Multimedia Channel (AMC) connector. The
AMC connector allows for direct attachment of external
devices to the graphics controller. This direct connection
facilitates transfer of video stream data from the controller
to the device, and vice versa.
Identifying the parts of the system board 8-3