The computer case contains the
framework to support the internal
components of a computer while
providing an enclosure for added
protection.
it is made of plastic, steel, or aluminum and are
available in a variety of styles.
As the air passes warm components, it
absorbs heat and then exits the case. This
process keeps the computer components from
overheating. Cases also help to prevent
damage from static electricity.
Power supplies
The power supply converts Alternating
Current (AC) power coming from a wall outlet into Direct
Current (DC) power, which is a lower voltage. DC power is
required for all components inside the computer.
The main three form factor
Power supplies, Advanced Technology (AT), AT
Extended (ATX), and ATX12V. The ATX12V is the most
common form factor used in computers today.
Connectors
A Molex keyed connector
A Berg keyed connector
A SATA keyed connector
A 20-pin or 24-pin slotted connector
A 4-pin to 8-pin auxiliary power connector
A 6/8-pin PCIe power connector
Electricity and Ohm’s Law
The four basic units of electricity
Voltage (V)
it is measure of work required to move a
charge from one location to another. Voltage
is measured in volts
Current (I)
it is measure of the amount of electrons moving through a
circuit per second. Current is measured in amperes, or
amps (A)
Power (P)
it is measure of the work required to move electrons through a
circuit (voltage), multiplied by the number of electrons going
through that circuit per second (current).
Resistance (R)
it is the opposition to the flow of current in a circuit, measured in ohms.
Lower resistance allows more current to flow through a circuit.
V = IR
It states that voltage is
equal to the current
multiplied by the
resistance
P = VI
The power is
equal to the
voltage multiplied
by the current
Internal PC components
Motherboard
The motherboard is the main printed circuit
board and contains the buses, or electrical
pathways, found in a computer.
These buses allow data to travel between the various
components that comprise a computer.
The motherboard
accommodates the central
processing unit (CPU), random
access memory (RAM),
expansion slots, heat sink and
fan assembly, basic
input/output system (BIOS)
chip, chipset, and the circuitry
that interconnects the
motherboard components.
CPUs
The central processing unit (CPU) is considered
the brain of the computer. It is sometimes referred to
as the processor.
Cooling Systems
The flow of current between the electronic
components generates heat. Computer
components perform better when kept cool.
ROM
Read-only memory chips. Information is written to a ROM chip when it
is manufactured. A ROM chip cannot be erased or re-written and is
obsolete.
RAM
RAM is the temporary storage for data and programs that are being accessed by the CPU.
RAM Types
Dynamic RAM
Static RAM
Synchronous DRAM
Fast Page Mode DRAM
Extended Data Out RAM
Double Data Rate SDRAM
Double Data Rate SDRAM
Double Data Rate 3 SDRAM
RAMBus DRAM
Memory Modules
Memory modules can
be single-sided or
double-sided.
Single-sided memory
modules contain RAM
only on one side of
the module.
Double-sided memory
modules contain RAM
on both sides.
Memory Modules types
DIP
Dual Inline
Package is
an individual
memory chip.
A DIP has
dual rows of
pins used to
attach it to
the
motherboard.
SIMM
Single Inline Memory Module is a small
circuit board that holds several memory
chips. SIMMs have 30-pin or 72-pin
configurations
DIMM Memory
Dual Inline Memory Module is a circuit board
that holds SDRAM, DDR SDRAM, DDR2 SDRAM,
and DDR3 SDRAM chips. There are 168-pin
SDRAM DIMMs, 184-pin DDR DIMMs, and
240-pin DDR2 and DDR3 DIMMs.
RIMM
RAMBus Inline
Memory Module is a
circuit board that
holds RDRAM
chips. A typical
RIMM has a 184-pin
configuration.
SODIMM
Small Outline
DIMM has a
72-pin and
100-pin
configurations
for support of
32-bit transfers
or a 144-pin,
200-pin, and
204-pin
configurations
for support of
64-bit transfers
Adapter Cards
and Expansion
Slots
Adapter cards increase the functionality
of a computer by adding controllers for
specific devices or by replacing
malfunctioning ports.
Adapter card types
Network
Interface
Card (NIC)
Connects a
computer to a
network using
a network
cable.
Wireless NIC
Connects a computer to a
network using radio
frequencies.
Sound adapter
Provides
audio
capability.
Video adapter
Provides
graphic
capability.
Capture card
Sends a video signal to a
computer so that the signal
can be recorded to the
computer hard drive with
Video Capture software.
TV tuner card
Provides the ability to watch and record
television signals on a PC by connecting
a cable television, satellite, or antenna
to the installed tuner card.
Storage Devices
Floppy drive
Hard drive
optical Drive
Flash Drive
Video Ports and Cables
Digital Visual Interface (DVI
it has 24 pins for digital signals and 4 pins for analog signals.
Displayport
it has 20 pins and can be used
for audio, video, or both audio
and video transmission.
RCA connectors
have a central plug with a ring around it and can be used to carry audio or video