This document provides instructions for assembling a computer. It discusses selecting and installing components like the power supply, motherboard, CPU, RAM, drives, expansion cards, and case fans. It emphasizes safety precautions and ensuring components are compatible. The proper installation of these parts includes connecting the front panel cables and power button to the motherboard to finish the assembly process.

1. Chapter 2: PC
Assembly
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2. Chapter 2 - Sections & Objectives
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 2.1 Assemble the Computer
• Build a computer.
– Define general and fire safety standards.
– Connect the power supply.
– Install the motherboard components.
– Install internal drives.
– Install the adapter cards.
– Identify additional storage.
– Connect computer components with appropriate cables.

3. 2.1 ASSEMBLE THE COMPUTER
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4. Personal, Equipment, and Fire Safety
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 Personal, equipment, and fire safety precautions while working in a computer:
• Remove watches, jewelry, and loose clothing
• Turn off and unplug equipment
• Remove clutter from workspace
• Proper lifting procedures
• Cover sharp edges inside the computer
• Wear safety goggles
• ESD safety and proper use
• Fire extinguisher availability, rating, and use (P-A-S-S)
• First Aide availability and use
• Component storage and handling

5. Select the Case and Fans
vents in the system case to facilitate positive air flow.
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• Model Type – The motherboard determines the type of case you can use. The
size and shape must match.
• Size – A computer with many components will need more room for airflow to
keep the system cool.
• Power Supply – Match the power supply rating and connection type to the
motherboard.
• Appearance – There are many case designs to choose from.
• Status Display – LEDs mounted on outside of case tell you if the system has
power, when the hard drive is in use, and when the computer is in sleep or
hibernate mode.
• Vents/Fans – All cases have a vent for the power supply, and some have extra

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Select a Power Supply
 Factors to consider when choosing a power supply
• Type of Motherboard – The power supply must be compatible with the
motherboard.
• Required Wattage – Add the wattage for each component. If the wattage is not
listed on a component, calculate it by multiplying its voltage and amperage. If
the component requires different levels of wattage, use the higher requirement.
• Number of components – Make sure the power supply provides enough
wattage to support the number and types of components plus another 20% at a
minimum.
• Type of components – Make sure the power supply provides the right types of
power connectors.
• Type of case – Make sure the power supply can be mounted in the desired
case.

7. Select the Case and Fans
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 Factors to consider when choosing a case fan:
• Case size – Larger cases often require larger fans because smaller fans cannot create
enough air flow.
• Fan speed – Larger fans can spin more slowly than smaller fans, which reduces fan
noise.
• Number of components – Multiple components in a computer create additional heat,
which requires more fans, larger fans, or faster fans.
• Physical environment – The case fans must be able to disperse enough heat to keep
the interior of the case cool.
• Number of mounting places available – Different cases have different numbers of
mounting places for fans.
• Location of mounting places available – Different cases have different locations for
mounting fans.
• Electrical connections – Some case fans are connected directly to the motherboard,
while others are connected directly to the power supply.

8. Open the Case and Connect the Power Supply
 Install the Power Supply
• Modern cases include a specific area for the power supply.
• Consult the case and power supply’s manuals
for more information.
• Align the holes in the power supply with the holes in the case.
• Secure the power supply to the case using
the proper screws.
• Make sure that all the screws are in place and tightened
correctly.
• Use a cable tie to secure all the cables out of the way.
• A modular power supply will help eliminate cable clutter
within a computer case.
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9. Select the Motherboard
 Factors to consider when choosing a motherboard:
• CPU socket type and speed
• RAM type and amount
• Front-side Bus speed
• Capabilities
– Chipset
– Expansion slots
– I/O ports
– Built-in ports
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10. Select a Replacement Motherboard
 When selecting a replacement motherboard,
make sure that it supports or accommodates:
• CPU
• RAM
• Video adapter, other adapter cards
• Socket and chipset on motherboard are
compatible with the CPU.
• The existing heat sink and fan assembly when reusing the CPU .
• The number/type of expansion slots. They must match the existing adapter
cards and allow for new cards.
• The existing power supply connections must fit the new motherboard.
• New motherboard must fit into the current computer case.
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11. CPU Socket Types
 Land Grid Array (LGA)
• Most common type of CPU today
• Pins are in the socket and receptacles on the CPU
• Allows for a higher pin density
• Inserted into a Zero Insertion Force (ZIF) socket
mounted on the motherboard
 Pin Grid Array (PGA)
• Pins are on the CPU and receptacles in the socket
 Ball Grid Array (BGA)
• CPU is soldered to the motherboard
• Usually found in laptops, phones, and tablets
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12. Select the CPU and CPU Cooling
 Selecting the CPU
• Socket type
• Speed
• Capabilities
 Selecting a Heat Sink
• Physical specifications – Must match the socket type
and not interfere with any other components attached
to the motherboard.
• Case size – Must fit within the case.
• Physical environment – Must be able to disperse
enough heat to keep the CPU cool.
• Active or Passive
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13. Types of RAM
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 DRAM
• Dynamic Random Access Memory
• Uses capacitors that need constant power to keep them from fading
• This process of charging is called Refresh
• Most DRAM needs to be refreshed every 2 ms
• Small and affordable, but slower than SRAM
 SRAM
• Static Random Access Memory
• Uses transistors
• Large and expensive, but fast
• Commonly used as cache

14. Types of RAM
 DIP (Dual Inline Pin)
• Small amount of memory (>1MB)
 SIPP (Single Inline Pin Package)
• Extinct because the pins were easy to bend and break
 SIMM (Single Inline Memory Module)
• Two different styles – 30 pin and 72 pin
 DIMM (Dual Inline Memory Module)
• 168 pins long (84 contacts per side)
• Also called SDRAM (Synchronous DRAM)
• Runs at the same speed as the FSB
• 64 bit data bus
• +3.3v
DIP
SIPP
30-pin SIMM
72-pin SIMM
168-pin DIMM or SDRAM
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15. Types of RAM
 DDR-SDRAM (Double Data Rate Synchronous DRAM)
• Twice as fast as SDRAM (if used in dual channel
configuration)
• Will not interchange with SDRAM
• 64 bit data bus
 DDR2
 DDR3
 DDR4
 DDR5
 SODIMM (Small Outline DIMM)
• Found in laptops and notebooks
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16. Select the RAM
 The RAM must be compatible with the motherboard.
 The speed of the RAM must be supported by the chipset.
 New RAM may be needed when an application locks up or the computer displays
frequent error messages. To determine if the problem is the RAM, execute the
RAM test in the BIOS.
 Memory may also be categorized as unbuffered or buffered:
• Unbuffered memory – This is regular memory for computers. The computer
reads data directly from the memory banks making it faster than buffered
memory.
• Buffered memory – Specialized memory for servers
and high-end workstations that use a large amount of
RAM. These have a control chip built into the module
that assists the memory controller in managing large quantities of RAM.
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17. Attach Components to the Motherboard
 CPU
• Easier to installed the CPU on the motherboard before the
motherboard is installed in the computer case.
• The CPU and motherboard are sensitive to electrostatic
discharge. Take antistatic precautions.
• Use the markings on the CPU and motherboard to properly
align and install the CPU.
• The CPU is secured to the socket on the motherboard with
a locking assembly.
• CAUTION: When handling a CPU, do not touch the CPU
contacts.
• Be sure the heat sink and fan assemble are correctly
installed.
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18. Attach Components to the Motherboard
 Thermal compound
• Helps keep the CPU cool and dissipate CPU heat.
• To install or reseat a used CPU, clean it and the base of the
heat sink with isopropyl alcohol to remove the old thermal
compound before applying new.
 Heat Sink/Fan Assembly
• The Heat Sink/Fan Assembly is a two-part
cooling device.
– The heat sink draws heat away from the CPU.
– The fan draws heat away from the heat sink.
• Be sure the heat sink and fan assemble are correctly
installed.
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19. Attach Components to the Motherboard
 RAM
• Easier to installed RAM on the motherboard
before the motherboard is installed in the
computer case.
• RAM is highly sensitive to ESD.
• RAM is designed to install in one specific direction. The notch in the memory
module should be aligned with a notch in the memory slot.
• Make sure to check the markings before applying pressure.
• Use the documentation provided with the motherboard and RAM for more
information on RAM installation.
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20. Install the Motherboard
 Install the Motherboard
• When the CPU, heat sink, fan and RAM are installed on the motherboard, the
motherboard can be installed in the case.
• Plastic and metal standoffs are used to mount the motherboard at the correct
height, to prevent it from touching the metal portions of the case and ground the
motherboard to the case.
• The I/O connectors on the back of the motherboard
should be aligned with the openings in the I/O plate.
The I/O connector plate or Backplane makes the I/O
ports of the motherboard available for connection in a
variety of computer cases.
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21. Select Hard Drives
 Selecting a Hard Drive
• Internal or external
• HDD, SSD, SSHD (hybrid)
• Hot-swappable
• Heat generation
• Noise generation
• Power requirements
• 3.5” or 2.5”
• HDD RPMs or 5400, 7200, or 10,000
• Interfaces:
– IDE (PATA)
– SATA (newest and fastest)
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22. Select Optical Drives
 Selecting an Optical Drive
 Connector type
 Reading capability
 Writing capability
 Optical media type
 5.25”
Optical Drive Capabilities
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23. Install the Hard Drive
 Install the Internal Drive
• Internal drives are installed in
empty hard drive bays found in
the case.
• The empty bay must match the
drive’s size.
• Leave some space between
the drives when installing
multiple drives.
• The drive’s metal plate should
face up to allow better heat
dissipation.
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24. Install the Optical Drive
 Step 1. From the front of the case, choose the drive bay
that you want to hold the drive. Remove the faceplate
from that bay if necessary.
 Step 2: Position the optical drive so that it aligns with the
5.25 inch (13.34 cm.) drive bay opening at the front of
the case, as shown in the figure.
 Step 3. Insert the optical drive into the drive bay so that
the optical drive screw holes align with the screw holes
in the case.
 Step 4. Secure the optical drive to the case using the
proper screws.
 Installation Tip: Slightly hand-tighten all the screws
before tightening any of them with a screw driver. This
will make it easier to tighten the last two screws.
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25. Motherboard Expansion Slots
 Common Expansion slots found on a motherboard:
• AGP – Accelerated Graphic Port
– Has 1x, 2x, 4x, 8x speeds
• PCI – Peripheral Component Interconnect
– Can connect up to five external components
– Uses a parallel expansion bus
• PCIe – PCI Express
– Has 1x, 4x, 8x, 16x slots
– Each type is a different length
– Has the highest transfer speed of any expansion slot
– Sends data one bit at a time over a serial bus
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26. Other Factors for Adapter Card Selection
 Adapter cards are designed for a specific task and add extra functionality to a computer.
There are a variety of adapter cards:
• Graphics/Video
• Sound
• Storage Controller
• I/O
• NIC
• Capture
 Before purchasing an adapter card, consider the following questions:
• What are the user’s current and future needs?
• Is there an open and compatible expansion slot available?
• What are the possible configuration options?
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27. Install the Adapter Cards
 Expansion cards are installed into an
appropriate slot on the motherboard.
• Installation Tip: Research the length of the
video card. Longer cards may not be
compatible with certain motherboards. Some
adapter cards may come with mounting
brackets of different heights to accommodate
these cases.
• Installation Tip: Some cases have small slots
at the bottom of the hole where the cover was
removed. Slide the bottom of the mounting
bracket into this slot before seating the card.
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28. Select a Media Reader
 Several media card formats have been developed over the years including:
• Secure digital (SD
• MicroSD
• MiniSD
• CompactFlash
• Memory Stick
 Choose a media reader based on current and
future needs:
• Media cards supported
• Internal or external
• Media size
• Connector type
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29. Select External Storage
 External USB flash drives, sometimes called thumb drives, are commonly used as
removable external storage. External storage devices connect to an external port
using USB, eSATA, or Thunderbolt ports.
 Choose the correct type of external storage for your customer’s needs. For
example, if your customer needs to
transfer a small amount of data, such as
a single presentation, an external flash
drive is a good choice. If your customer
needs to back up or transfer large
amounts of data, choose an external
hard drive.
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30. Install the Front Panel Cables
 A computer case typically
has a power button and
visible activity lights on the
front of the case. The case
will include front panel
cables that must be
connected to a common
system panel connector on
a motherboard. Writing on
the motherboard near the
system panel connector
shows where each cable is
connected.
Front Panel Connectors
System Panel Connector
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31. Install the Front Panel Cables
 System panel connectors include:
• Power Button
• Reset Button
• Power LED
• Drive Activity LEDs
• System Speaker
• Audio
 System panel connectors are not keyed. However, each front panel cable usually
has a small arrow indicating pin 1, and each pair of LED pins on the motherboard
system panel connector has pin 1 marked with a plus sign (+).
Pin 1 Arrow Indicator System Panel Connector Pin 1 Indicator
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32. Install the Front Panel Cables
 New cases and motherboards have USB 3.0,
USB 3.1, or USB 4.0 capabilities.
 USB connector cables are often 9 or 10 pins
arranged in two rows. These cables connect
to USB motherboard connectors. This
arrangement allows for two USB connections,
so USB connectors are often in pairs.
 Sometimes the two connectors are together in
one piece and can be connected to the entire
USB motherboard connector.
USB Motherboard Connectors
Internal USB Connector
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33. Install the Front Panel Cables
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 Power Button – Align pin 1 of the two-pin front panel power button cable with the power
button pins on the motherboard.
 Reset Button – Align pin 1 of the two-pin front panel reset button cable with the reset button
pins on the motherboard.
 Power LED – Align pin 1 of the front panel power LED cable with the
power LED pins on the motherboard.
 Drive Activity LED – Align pin 1 of the front panel drive activity cable with the drive activity
pins on the motherboard.
 System Speaker – Align pin 1 of the front panel system speaker cable with
the system speaker pins on the motherboard.
 Audio Cables – Due to the specialized function and variety of the hardware, consult the
motherboard, case, and audio panel documentation for specific instructions.
 USB – Align pin 1 of the USB cable with the USB pins on the motherboard.

34. Connect Internal Cables
 Power cables are used to distribute electricity from the power supply to the
motherboard and other components.
 PCIe may take an additional 6 or 8-pin power connector.
 High-end video cards may take up to 2 8-pin power connectors.
ATX
AUX Berg
SATA Molex
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35. Install the Cables
 Connect Power to Motherboard
• Motherboards require power to operate.
• Motherboards also relay power to components and adapter cards.
• Refer to the motherboard and power supply documentation to ensure
compatibility of power supply and motherboard connectors.
• Modern motherboards require two power connectors for operation.
• Align the proper connectors and press it
down against the motherboard.
• Remember: If it is difficult to plug in a cable
or other part, something is wrong.
Do not use more force.
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36. Install the Cables
 Connect Power to the Internal Drive and Case Fans
• Some drives accept different power connectors for compatibility.
• 4-pin Molex and 15-pin SATA are common hard drive connectors.
• Align the proper connectors and gently press it against the other end.
• Fans also need power and use 3-pin or 4-pin connectors.
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37. Connect Internal Cables
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 Data cables transmit data between the motherboard and storage devices, such
as hard drives. Some of examples of this type of cables are:
• PATA cable (40-pin IDE or EIDE)
• SATA cable (7-pin)
• Floppy drive data cable (34-pin)
 Connect the Internal Data Cables
• The internal and optical drives typically connect to the motherboard through
SATA cables.
• SATA are keyed to fit in only one direction. They also have locking tabs.
• Locate the SATA socket on the motherboard, align the connector and press it
gently to connect.

38. 2.2 CHAPTER SUMMARY
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39. Chapter 2: PC Assembly
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 Build a computer.
• Define general and fire safety standards.
• Connect the power supply.
• Install the motherboard components.
• Install internal drives.
• Install the adapter cards.
• Identify additional storage.
• Connect computer components with appropriate cables.

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