The motherboard holds many important computer components and determines the layout and size of the system. Common form factors include ATX, LPX, and NLX. The CPU executes instructions to carry out programs and its speed is measured in GHz. RAM allows data to be accessed quickly and comes in types like SRAM, DRAM, SDRAM, and DDR SDRAM. The power supply provides power to all components in regulated voltages of 3.3v, 5v, and 12v.

1. P1 – Identify And Explain The
Functions Of Common Components Of
A Computer System:
Ryan Parish

2.  A motherboard is a printed circuit board found in computers and other expandable systems. The purpose of the motherboard is it
holds many of the important components of the system.
 The form factor determines the general layout, size, and feature placement on the motherboard. The differences between form
factors can include: physical size and shape, mounting hole location, feature placement, power supply connectors, and others.
 ATX - ATX was developed as an evolution of the Baby AT form factor and it was defined to address four areas of improvement:
enhanced ease of use, better support for current and future I/O, better support for current and future processor technology, and
reduced total system cost.
 LPX - LPX is an older form factor that has been replaced by NLX. The LPX form factor is usually found in desktop model PCs. The LPX
case is a slim-line, low-profile case with a riser card arrangement for expansion cards.
 NLX - NLX is a new low profile motherboard form factor designed to improve today’s low profile form factors and to adapt to new
market trends and PC technologies. NLX does the following:
 Supports current and future processor technologies.
 Supports new Accelerated Graphics Port (A.G.P.) high performance graphics solutions.
 Supports tall memory technology.
 Provides more system level design and integration flexibility; for example, the new design flexibility allows system designers to
implement a motherboard that can be removed quickly, in most cases without removing screws, thus lowering the PC’s total cost of
ownership.
Motherboard:

3.  The CPU (Central Processing Unit) is the hardware inside a computer that carries out the instructions of a computer program. It is
the brain of the computer. CPU’s are created by Intel and AMD.
 One of the most important things about CPUs is it’s speed. The speed of a CPU is measured in Hz. Now we usually use MHz because
the CPUs are too fast to measure in Hz. Because of the extremely high speed of CPU, computers can do millions of operation in a
short period of time. Heat is released when CPUs run. High temperature decreases the performance of a CPU. This means you need
a fan to cool down the CPU. You can change the speed of CPU in BIOS of your computer.
 Overclocking is the process of making a computer component operate faster than the clock frequency specified by the
manufacturer by modifying system parameters.
 In a single-core the CPU is fed strings of instructions it must order, execute, then selectively store in its cache for quick retrieval.
When data from outside the cache is required, it is retrieved through the system bus RAM or from storage devices.
 In a dual core processor, each core handles incoming data strings repeatedly to improve the efficiency. Now when one is executing
the other can be accessing the system bus or executing its own code. Adding to this favourable scenario, both AMD and Intel's dual-
core flagships are 64-bit.
 A quad-core processor is a chip with four independent units called cores that read and execute CPU instructions such as add, move
data, and branch. Within the chip, each core operates in conjunction with other circuits such as cache, memory management, and
input and output ports. The individual cores in a quad-core processor can run multiple instructions at the same time, increasing the
overall speed for programs compatible with parallel processing.
CPU:

4.  The RAM (Random Access Memory) allows stored data to be accessed in the same amount of time for any storage location, so data
can be accessed quickly in any order.
 SRAM: Static random access memory uses multiple transistors, typically four to six, for each memory cell but doesn't have a
capacitor in each cell. It is used primarily for cache.
 DRAM: Dynamic random access memory has memory cells with a paired transistor and capacitor requiring constant refreshing.
 FPM DRAM: Fast page mode dynamic random access memory was the original form of DRAM. It waits through the entire process of
locating a bit of data by column and row and then reading the bit before it starts on the next bit. Maximum transfer rate to L2 cache
is approximately 176 MBps.
 EDO DRAM: Extended data-out dynamic random access memory does not wait for all of the processing of the first bit before
continuing to the next one. As soon as the address of the first bit is located, EDO DRAM begins looking for the next bit. It is about
five percent faster than FPM. Maximum transfer rate to L2 cache is approximately 264 MBps.
 SDRAM: Synchronous dynamic random access memory takes advantage of the burst mode concept to greatly improve
performance. It does this by staying on the row containing the requested bit and moving rapidly through the columns, reading each
bit as it goes. The idea is that most of the time the data needed by the CPU will be in sequence. SDRAM is about five percent faster
than EDO RAM and is the most common form in desktops today. Maximum transfer rate to L2 cache is approximately 528 MBps.
 DDR SDRAM: Double data rate synchronous dynamic RAM is just like SDRAM except that is has higher bandwidth, meaning greater
speed. Maximum transfer rate to L2 cache is approximately 1,064 MBps.
RAM:

5.  The power supply supplies all of the power to the computer. A regulated power supply is one that
controls the output voltage or current to a specific value; the controlled value is held nearly constant
despite variations in either load current or the voltage supplied by the power supply's energy source.
 These are the four basic units of electricity:
 Voltage (V)
 Current (I)
 Power (P)
 Resistance (R)
 AC stands for Alternating Current, a type of electricity that changes constantly from one polarity to
another. DC stands for Direct Current, a type of electricity that maintains its polarity all theAN AC/DC
converter is something that turns outlet-type electricity into battery type electricity. Rectifier’s can
convert AC to DC. The different types of rectifiers are half wave, full wave and bridge rectifier.
 The three different voltages for computers are: 3.3v, 5v and 12v.
Power Supply:

6.  The heat sink is the component that cools a device by dissipating
heat into the air. In a computer the heat sink is used to cool the
central processing unit and graphics processers. A heat sink
without a fan is called a passive heat sink; a heat sink with a fan is
called an active heat sink. Heat sinks are generally made of an
aluminium alloy and often have fins.
Heat Sink:

7.  The graphics card is an expansion card that which creates a feed
of output images to a display. The better the graphics card a
computer has the better the graphics will be. Most video cards
offer various functions such as accelerated rendering of 3D
scenes and 2D graphics. Because graphics cards work hard they
generate heat. For this reason most high-performance video
cards utilize built-in fans. Fans can be quiet or noisy, depending
on the card model. High-performance fanless video cards are also
available. These cards use heat sinks to pull heat away from the
GPU (Graphics Processing Unit).
Graphics Card:

8.  A sound card is an internal computer expansion card that
facilitates the input and output of audio signals to and from a
computer under control of computer programs. Typical uses of
sound cards include providing the audio component for
multimedia applications such as music composition, editing video
or audio, presentation, education and games and video
projection.
Sound Card:

9.  The hard drive is a storage device used to store and receive digital information using a spinning disk which are coated with a
magnetic material.
 Hard disk drives are accessed over one of a number of bus types, including as of 2011 parallel ATA (PATA, also called IDE or EIDE;
described before the introduction of SATA as ATA), Serial ATA (SATA), SCSI, Serial Attached SCSI (SAS), and Fibre Channel. Bridge
circuitry is sometimes used to connect hard disk drives to buses with which they cannot communicate natively, such as IEEE 1394,
USB and SCSI.
 IDE (Integrated Drive Electronics) is a standard electronic interface used between a computer motherboard's data paths or bus and
the computer's disk storage devices. The IDE interface is based on the IBM PC Industry Standard Architecture 16-bit bus standard,
but it is also used in computers that use other bus standards.
 Enhanced IDE is a standard electronic interface between your computer and its mass storage drives. EIDE's enhancements to
Integrated Drive Electronics make it possible to address a hard disk larger than 528 Mbytes. EIDE also provides faster access to the
hard drive, support for Direct Memory Access , and support for additional drives, including CD-ROM and tape devices through the
AT Attachment Packet Interface.
 Serial ATA (SATA) is a computer bus interface for connecting host bus adapters to mass storage devices such as hard disk drives and
optical drives.
 Small Computer System Interface is a set of standards for physically connecting and transferring data between computers and
peripheral devices. The SCSI standards define commands, protocols, and electrical and optical interfaces.
Hard Drive:

10.  An optical disk drive (ODD) is a disk drive that uses a laser light or
electromagnetic waves as part of the process of reading or
writing data to and from optical disks. Some drives can only read
from discs, but recent drives are commonly both readers and
recorders, also called burners or writers.
Optical Drive:

11.  The Northbridge is used to manage the data communications
between the CPU and a motherboard within Intel chipsets. It is
designed to be paired with a second support chip known as a
Southbridge. The Northbridge has historically been one of the
two chips in the core logic chipset on a PC motherboard, the
other being the Southbridge. Increasingly these functions have
migrated to the CPU chip itself, beginning with memory and
graphics controllers.
Northbridge:

12.  The Southbridge is one of the two chips in the core logic chipset
on a personal computer (PC) motherboard, the other one is the
Northbridge. The Southbridge implements the slower capabilities
of the motherboard in a northbridge/southbridge chipset
computer architecture. The Southbridge can usually be
distinguished from the Northbridge by not being directly
connected to the CPU. Rather, the Northbridge ties the
Southbridge to the CPU.
Southbridge:

13.  BIOS (Basic Input/output System) is a Program that checks that all
hardware is present and working properly when the computer is
booting up. The BIOS provides a consistent way for application
programs and operating systems to interact with the keyboard,
display, and other input/output devices. The fundamental
purposes of the BIOS are to initialize and test the system
hardware components, and to load an operating system or other
program from a mass memory device.
BIOS:

14.  Memory module is a broad term used to refer to a series of dynamic random access memory integrated circuits modules mounted
on a printed circuit board and designed for use in personal computers, workstations and servers.
 Cache memory is random access memory that a computer microprocessor can access more quickly than it can access regular RAM.
As the microprocessor processes data, it looks first in the cache memory and if it finds the data there, it does not have to do the
more time-consuming reading of data from larger memory.
 It can be used to these specific types of memory module:
 Dual in-line package memory.
 Trans Flash Memory Module.
 SIPP memory, single in-line pin package memory.
 SIMM, a single in-line memory module.
 DIMM, dual in-line memory module.
 Rambus memory modules are a subset of DIMMs, but are usually referred to as RIMMs.
 SO-DIMM, small outline DIMM, a smaller version of the DIMM, used in laptops.
 Distinguishing characteristics of computer memory modules include voltage, capacity, speed, and form factor.
Memory Modules:

15.  Complementary metal–oxide–semiconductor (CMOS) is a technology for
constructing integrated circuits. CMOS technology is used in microprocessors,
microcontrollers, static RAM, and other digital logic circuits. CMOS technology
is also used for several analog circuits such as image sensors (CMOS sensor),
data converters, and highly integrated transceivers for many types of
communication. In a computer, the CMOS controls a variety of functions,
including the Power On Self Test (POST). When the computer’s power supply
fires up, CMOS runs a series of checks to make sure the system is functioning
properly.
CMOS: