Motherboard
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Section Objectives
 Define the purpose of the major components on a motherboard
including the CPU, chipset, and expansion slots
 Explain the basic operation of a microprocessor and what
issues must be considered when upgrading it
 Recognize and identify the motherboard, CPU and expansion
slots
 Compare and contrast motherboard buses and expansion slots
 Identify methods to add functionality to portable devices.
Explain different motherboard technologies such as MMX,
HypterTransport, HyperThreading, and dual/quad-core
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Microprocessor Overview
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Microprocessor (or processor)
CPU (Central Processing Unit)
Clones – IBM compatibles
PC – Stands for Personal Computer, another name for the microcomputer.
 Intel and AMD are the microprocessors primarily used in today’s computer
industry.
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Microprocessor Basics
 Bit – Either a 1 or 0. All microprocessors use 1s and 0s to calculate or
interpret information.
 Byte – Eight bits grouped together, the letter A looks like 01000001 to the
processor. Each character on the keyboard appears as one byte (or eight bits)
to the CPU. Denoted by the letter B, thirty-two bytes is 32B.
 Kilobyte – Approximately 1,000 bytes (1,024 exactly, but rounded off by the
industry to the nearest thousand for ease of calculation). Shown as K or KB,
ten kilobytes is shown as 10K or 10KB.
 Megabyte – Approximately one million bytes and referenced by M or MB.
540 megabytes is shown as 540M or 540MB.
 Gigabyte – Approximately 1 billion bytes (1,073,741,824) and written as 1G
or 1 GB.
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Microprocessor Basics
Byte Table
Motherboard – Table 2.1
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Microprocessor Basics
• Gigahertz (GHz) – Hertz is a measurement of cycles per second (or
frequency). One hertz equals one cycle per second. One gigahertz (1GHz) is
one billion cycles per second.
• Register size – The number of bits processed at one time by the processor.
Counted in multiples of 8 bits, such as 8-, 16-, and 32-bit register size.
Sometimes referred to as word size by the computer industry. Most
microprocessors today have 64-bit or 128-bit register sizes.
• Bus – Electronic lines to move the 1s and 0s inside the computer.
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Microprocessor Basics
 Internal data bus – Moves the 1s and 0s inside the
microprocessor.
 External data bus – Used to connect the microprocessor to
adapters, storage devices, and peripherals. Also called the
external data path, these lines connect to ports and expansion
slots.
 Today’s microprocessors have 64-bit or 128-bit internal data
bus lines and external data paths.
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Microprocessor Basics
Internal and External Data Buses
Motherboard – Figure 2.1
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Microprocessor Basics
Intel Microprocessors
Motherboard – Table 2.3
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Microprocessor Basics
 ALU (Arithmetic Logic Unit) – Component of the processor which carries
out calculations and comparison logic.
 Pipelines – Separate (multiple) internal buses that operate simultaneously.
This allows tasks and instructions to be broken down into smaller and more
numerous parts, which permits the CPU to act on them more quickly and
efficiently, improving computer performance.
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Microprocessor Basics
Motherboard – Table 2.4
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Microprocessor Basics
Motherboard – Figure 2.2
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AMD Processors
 AMD (Advanced Micro Devices, Inc.) – Produces a
microprocessor similar to the Intel processors.
 Socket A – 462-pin PGA socket for the AMD Athlon and
Duron CPUs.
 Slot A – Used by early AMD Athlon processors similar to Intel
Pentium III, but they are not interchangeable.
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AMD Processors
Motherboard – Figure 2.3
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Cache Memory
 Cache memory – A fast type of memory designed to increase the speed of
microprocessor operations.
 L1 (Level one) cache – Cache memory that is located inside the
microprocessor.
 L2 cache – Cache memory that is inside the processor packaging but not part
of the CPU, also known as on-die cache.
 L3 cache – Cache memory located in the CPU housing or on the
motherboard.
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Cache Memory
Motherboard – Figure 2.4
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Clocking
 Clock Signal – Generated by the motherboard and used to
control transfer of 1s and 0s to CPU.
 Multiplier – A number that is multiplied by the bus speed to
determine the CPU speed.
Example: 60MHz bus speed x 1.5(multiplier) = 90MHz
CPU
 Jumper – Small metal connector with a plastic cover used to
connect two metal pins together. Configuring the jumpers on a
motherboard will change the settings on that board.
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Jumper
Motherboard – Figure 2.8
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Dual and Quad Processors
 Dual-core CPU – Combines two CPUs on a single unit.
 Quad-core CPU – Either two dual-core CPUs installed on the
same motherboard or two dual-core CPUs installed in a single
socket.
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AMD dual-core memory access
Motherboard – Figure 2.9
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Intel dual-core memory access
Motherboard – Figure 2.10
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Sockets and Slots
 Different types of sockets:
 PGA (pin grid array) – even rows of holes around the
square socket
 SPGA (staggered pin array) – staggered holes
 PPGA (plastic pin grid array) – used on Intel Celerons and
Pentium 4s
 µPGA (micro pin grid array) – used by AMD Opterons and
various Athlon 64s
 LGA (land grid array) – used with AMD Opterons and Intel
Pentiums 4s and Xeons
 ZIF sockets (Zero Insertion Force) – processor sockets used
today
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LGA775 socket
Motherboard – Figure 2.11
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Processor Speeds and Cooling
 Many processors now have heat sinks (metal bars protruding from the CPU to form a
basic radiator) and/or small fans. Some systems have multiple fans.
 Liquid cooling system – Liquid is circulated through the system, including through a
heat sink that is mounted on the CPU. It allows higher clock speeds and is quieter
than a fan.
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CPU fan and heat sink
Motherboard – Figure 2.12
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Installing Microprocessors
Always refer to the motherboard manuals for
the installation steps to upgrade or install the
processor. Your manual contains general
instructions for upgrading and installing the
microprocessor .
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Installing an AMD CPU
Motherboard – Figure 2.16
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Overclocking Microprocessors
Overclocking – Changing the front-side bus
speed and/or the multiplier to boost the CPU
speed or system speed. This can cause damage
to the CPU, motherboard, or other components.
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MMX, SSE, and 3DNOW!
 MMX – A microprocessor technology from Intel that adds 57
instructions to an Intel processor to help with multimedia and
communications software.
 SSE (Streaming SIMD Extensions) – Intel’s processor
technology that speeds up 3-D applications by allowing
instructions to be used by multiple data items.
 3DNOW! – 21 instructions and support for SIMD added to an
AMD processor for 3-D applications.
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Expansion Slots
Expansion slots allow adapters to be installed
into the motherboard to add capabilities to the
PC.
You must be able to identify expansion slots
and distinguish between the adapters that use
them.
You must be able to install the proper adapter in
the correct expansion slot and configure both
correctly.
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Motherboard expansion slots
Motherboard – Figure 2.17
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ISA (Industry Standard Architecture)
 ISA (Industry Standard Architecture) – The oldest expansion
slot, is configured in 8-Bit and 16-Bit slots.
Motherboard – Figure 2.18
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PCI (Peripheral Component
Interconnect)
 PCI (Peripheral Component Interconnect) – The previously
popular expansion slot. It is configured in both 32-bit, 33MHz
and 64-bit, at 33MHz and 66MHz.
 A new standard is the PCI-X which can operate at 66MHz,
133MHz, 266MHz, 533MHz, and 1066MHz.
Figure 2.19
Figure 2.22
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AGP (Accelerated Graphics Port)
 AGP (Accelerated Graphics Port) – Bus interface for graphics adapters developed
from the PCI bus.
 It speeds up 3-D graphics, 3-D acceleration, and full-motion playback.
 The video subsystem is isolated from the rest of the computer.
 Allows the video adapter to directly access RAM on the motherboard when
needed.
Figure 2.23
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PCI-E (Peripheral Component
Interconnect-Express)
 PCI-E(Peripheral Component Interconnect-Express) – Also
known as PCIe. PCI-e is replacing PCI, PCI-X, and AGP
expansion slots.
 Hypertransport – Technology used by AMD, which is a highspeed bus used to connect multiple CPUs, interface and AMD
CPU with input/output devices, interface the CPU with PCI,
PCI-X, and PCI-E slots, and interface the CPU with RAM.
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PCI for the Laptop
 Mini PCI – 32-bit, 33MHz standard was developed to
allow PCI upgrades and interface cards to be added to
laptops, docking stations, and printers. Mini-PCI cards
have 3 form factors; Type I, Type II, and Type III.
 ExpressCard® – Latest high-performance, hardware
expansion standard for mobile computers. Replaces
PC cards. Provide the user the ability to add a variety
of plug‘n play applications.
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More Motherboard Connectors
 AMR (Audio/Modem Riser) – Connector on the motherboard
for combination audio and modem adapters without taking up a
PCI slot.
 CNR (Communications Network Riser) – Intel’s design that
allows the integration of network, audio, and modem functions.
It shares a PCI slot and is located beside or between other
motherboard expansion slots.
 ACR (Advanced Communication Riser) – Technology that
supports audio, modem, networking, and DSL modems. It was
developed by a group of companies including AMD, VIA
Technologies, Motorola, and 3Com.
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Proprietary Expansion Slots
Some older computers have an expansion slot
built into the motherboard that are neither ISA
nor PCI. These are proprietary expansion slots
that only fit proprietary adapter cards. These are
only available from the expansion slot
manufacturer (if still supported) and usually
expensive.
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Chipsets
Chipset – The principle chips on the
motherboard that work in conjunction with the
microprocessor and allow features on a
computer.
For example, they control:
–
–
–
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Maximum amount of motherboard memory
The type of RAM chips
The motherboard’s capacity for multiple processors
Support for the latest version of PCI
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Types of Motherboards
 Form Factors – The different sizes of motherboards.
 The common motherboards are:
– ATX: most common motherboard
– Different types of ATX include: microATX, miniATX, and
FlexATX
 Older form factors: AT, Baby AT, NLX, ITX, WTX
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Upgrading and Replacing Motherboards
 There are several issues to be taken into account when upgrading a motherboard:
– Memory
– Adapter types
– Type of case
– Microprocessor
– Chipsets
– Hard drive
– Power supply
– Future upgrade-ability
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Motherboard Troubleshooting
• Motherboard and power problems are some of
the most difficult to troubleshoot. One of the
most beneficial tools for troubleshooting the
motherboard is POST.
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