The midboard connectors are divided into the following functional groups: Audio/video This group of connectors is included on motherboards that
have sound, video, and CD-ROM support integrated into the motherboard.
The connectors included in this group typically include an auxiliary sound
line in, a telephony connection, a legacy CD-ROM connector, and an ATAPI
(AT Attachment Packet Interface) CD-ROM connection. These connectors and
their use are explained in more detail in Chapter 21.
Peripheral device interfaces Most newer motherboards and chipsets include
support for some peripheral devices to connect directly to the motherboard
through connectors mounted on the motherboard. These connections, shown
in Figure 19-3, include the primary and secondary IDE connectors used for hard
disk and CD-ROM drives and the floppy disk controller. These connectors are
discussed in more detail in Chapters 4 and 5.
Hardware power and management The connectors in this group are used to
attach the power supply to the motherboard, to provide support for Wake on
LAN or Wake on Ring technology, and to connect system and processor fans
to the system.
Memory slots While technically not a peripheral device connector, every
motherboard includes some form of connector, mounting, or slot for memory
chips or modules. Newer boards have slots for RIMMs (RDRAM inline
memory modules) and DIMMs (dual inline memory modules). Older
motherboards have slots for SIMMs (single inline memory modules) or
DIP (dual inline packaging) sockets.
Expansion slots Every PC motherboard includes at least a few expansion slots
that are used to add peripheral device adapter and interface cards to the PC. As
explained in Chapter 11, motherboards support a variety of expansion slot types,
but ISA (Industry Standard Architecture), PCI (Peripheral Components Interconnect),
and AGP (Accelerated Graphics Port) are the most common.Front Panel Connectors
As described in more detail in Chapter 15, the front panel of the system case can have a
variety of LEDs and switches that are attached to the motherboard for power or signals
that indicate various activities. Most motherboards include connectors for the hard disk
(power and activity), a main power on/off button, possibly a reset button, +5V DC power
connections, and grounding circuits. Most motherboards also have connections for the
system speaker (the one that sounds beeps and other tones, not the one used to play music).
Some motherboards also support an infrared or IrDA (Infrared Data Association) serial
port connector as well (more on IR connections later in the chapter).Chapter 19: Ports and Connectors^479