Task 2 Hardware Research
Research and explain the
function of the following 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 holds things
such as the central processing unit (CPU), RAM, expansion slots, heat sink/fan
assembly, BIOS chip, chipset, and the internal wires that all of these
components to the motherboard, and to the power supply. (1) The ROM BIOS is a collection of software utilities that forms some
of the operating system, on the ROM. The BIOS checks the actual hardware
configuration to the configuration data that is sorted on the computer, if
these don’t match then the BIOS lets the user know that they do not match, and
if it will be a problem or not. It ensures the reliability of the computer of
the computer system and can be used as an important diagnostic tool. (25)
Power
Supply
The internal 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 of the components inside the
computer. (2) An external power supply, a
raspberry pi, is powered by a USB port, using about 5 volts and 3.5 watts. It
does everything a computer does but it is just like the tower, and needs to be
plugged into a TV (as a monitor), and a keyboard. (3)
Hard
Drive
A hard drive is
a magnetic storage device that is installed inside the computer. The hard drive
is used as permanent storage for data. The storage capacity of a hard drive is
measured in billions of bytes, or gigabytes (GB). The speed of a hard drive is measured
in revolutions per minute (RPM). (4) The hard drive is connected
either by a SATA or PATA cable. The SATA cable is a much easier cable to
connect it with, as it is much smaller and allows a faster air flow, enabling a
quicker connection.
Optical
Drive
An optical drive is a storage device
that uses lasers to read data on the optical media. There are three types of
optical drives Compact Disc (CD), Digital versatile Disc (DVD) and Blu-ray Disc
(BD). CD’s have a data storage capacity of about 700MB, DVD’s have a storage of
about 4.3GB (on a single-layer disc) or about 8.5GB (on a dual-layer disc). BD
have a storage capacity of 25GB (on a single-layer disc) or 50GB (on a
dual-layer disc). These types of optical drives can
be pre-recorded (read-only), recordable (write once), or re-recordable (read
and write multiple times). (5)
Network
Interface Card (NIC)
A network interfaced card allows a network connection
using a network cable. (6) There are two
different types of NIC’s: wireless and wired. Wireless Network Interface Cards
have an external areal; an example of a wireless NIC is a TP-LINK 150mbps
Wireless N PCI Adapter. A wired NIC provides a connection between other
computers through a copper wire, usually an Ethernet cable, which plugs into
the designated RJ45 slots. Other NICs use fibre-optic cables, which actually
allow a faster connection because it uses light as appose to electricity.
However, whether the NIC is wired or wireless, all of them have a designated
Mac addresses that are programmed to the ROM chip on the NIC. The Mac address
allows the connection between computers, as computers need to know other
computers Mac addresses to enable them to send messages between the two. They convert the message into binary to be
send across the network, then change it back afterwards.
Video
Adapter
A video adapter provides graphic capability. The most
common Video Adapter Cards are AGP PCIE VGA DVI and HTMI.
AGP (Accelerated Graphics Port) is an interface which is based on PCI, but is
designed especially for the demands of 3D Graphics. Unlike the PCI, using a PCI
bus for graphics data, AGP uses a dedicated point-to-point channel, allowing the
graphics controller to directly access the main memory. The AGP channel is 32
bits wide and runs at 66MHz. AGP also supports two optional faster modes, with
throughputs of 533 MBps and 1.07 GBps. AGP also allows 3-D textures to be
stored in main memory rather than video memory. (7)
PCIE PCI Express is an Input Output interconnect bus standard
that expands on and doubles the data transfer rates of orginal PCI. A PCI
Express is a two-way, serial connection that carries data in packets alnog two
pairs of point-to-point data lanes. Initial bit rates of the PCI Express
reaches 2.5GB/s per lane direction, which equates to data transfer rates of
about 200MB/s. The PCI Express was made so that high-speed interconnects such
as 1394b, USB 2.0, InfiniBand and Gigabit Enthernet would have an Input Output
architecture suitable for their transfer high speeds. (8)
VGA A VGA (Video Graphics Array) is a graphics display system
for PCs. In text mode, VGA systems provide a resolution of 720 by 400 pixels.
In graphics mode, the resolution is either 640 by 480 (with 16 colours) or 320
by 200 (with 256 colours). With a total palette of colours is 262, 144. VGA
uses analog signals, rather than digital signals like old graphic standards
(such as MDA, CGA and EGA). (9)
DVI A DVI (Digital Video Interactive) enables a computer to
store and display moving video images. The most difficult aspect of displaying
TV-like images on a computer is the immense amount of stoage that each frame
requires (a single frame can require up to 2MB of storage). It’s also hard for
the computer to transmit data to the display screen at the same rate of a
Television (30 frames per second), and can exhaust a computer’s mass storage
resources. (10)
HDMI A HDMI (High-Definition Multimedia Interface) is an
all-digital audio/video interface. It provides an interface between any
audio/video source, such as a DVD player or an A/V reciever, and an audio
and/or video monitor, such as a digital television, over a single cable. HDMI
was defined to carry 8 channels, of 192kHz and 24-bit uncompressed audio. HDMI
has the capacity to support high-definition video formats such as 720p, 1080i,
and 1080p, along with support of enhanced definition formats like 480p. It also
has the capacity for the standard definition formats such as NTSC or PAL. (11)
Internal
Cables
Drives require both a power cable and a data cable.
A power supply will have a SATA power connector for SATA drives, a Molex power
connector for PATA drives, and a Berg 4-pin connector for floppy drives. The
buttons and the LED lights on the front of the case connect to the motherboard
with the front panel cables. Data
cables connect drives to the drive controller, which is located on an adapter
card or on the motherboard. For example;
·
Floppy Disk Drive (FDD) data cable – this
cable has up to two 34-pin drive connectors and one 34-pin connector for the
drive controller
·
PATA (IDE/EIDE) 40-conductor data cable – the
IDE interface supported two devices on a single controller. However the EIDE
interface, two controllers capable of supporting two devices. The 40-conductor
ribbon cable uses 40-pin connectors. The cable has two connectors for the
drives and one connector for the controller
·
PATA (EIDE) 80-conductor data cable – the
80-conductor cable was introduced for devices transmitting at 33.3 MB/s and
over. This allowed a more reliable balanced data transmission. The 80-conductor
cable uses 40-pin connectors
·
SATA data cable – has seven conductors, one
keyed connector for the drive and one keyed connector for the drive controller
·
eSATA data cable – the eSATA external disk
connects to the eSATA interface using a 7-pin data cable. This cable doesn’t
supply power to the eSATA external disk, a separate power cable provides the
power to the external disk.
·
SCSI data cable – there are three types of
SCSI data cables. A narrow SCSI data cable has 50 conductors, up to seven
50-pin connectors for drives and one 50-pin connector for the drive controller
(also called the host adapter). A wide SCSI data cable has 68 conductors, up to
fifteen 68-pin connectors for drives and one 68-pin connectors for the host
adapter. An Alt-4 SCSI data cable has 80 conductors, up to fifteen 80-pin
connectors for drives and one 80-pin connector for the host adapter.
External
Cables
External cables connect external devices, such as hard
drives and peripherals.
USB A USB (Universal Serial Bus) is an
external bus standard that supports data transfer rates of 12 Mbps. A single
USB port can be used to connect up to 127 peripheral devices, such as mice,
modems and keyboards. USB is expected to completely replace serial and parallel
ports. (20)
VGA A VGA (Video Graphics Array) is a
graphics display system for PC’s. In text mode, VGA provides resolution of 720
by 400 pixels. In graphics mode, the resolution is either 640 by 480, with 16
colours, or 320 by 200, with 256 colours. With a total palette of colours is
262, 144. VGA uses
analog signals, rather than digital signals like old graphic standards (such as
MDA, CGA and EGA). (9)
DVI A DVI (Digital Video Interactive) enables a
computer to store and display moving video images. The most difficult aspect of
displaying TV-like images on a computer is the immense amount of storage that
each frame requires (a single frame can require up to 2MB of storage). It’s
also hard for the computer to transmit data to the display screen at the same
rate of a Television (30 frames per second), and can exhaust a computer’s mass
storage resources. (10)
HDMI A HDMI (High-Definition Multimedia Interface) is an
all-digital audio/video interface. It provides an interface between any
audio/video source, such as a DVD player or an A/V receiver, and an audio
and/or video monitor, such as a digital television, over a single cable. HDMI
was defined to carry 8 channels, of 192 kHz and 24-bit uncompressed audio. HDMI
has the capacity to support high-definition video formats such as 720p, 1080i,
and 1080p, along with support of enhanced definition formats like 480p. It also
has the capacity for the standard definition formats such as NTSC or PAL. (11)
Ethernet
Cable
An
Ethernet cable is one of the most popular forms of network cable used on wired
networks. Ethernet cables connect devices on local area networks such as PCs,
routers and switches. The most common Ethernet cables are Category 5 (CAT5) and
Category 6 (CAT6). A crossover cable is a special type of Ethernet cable
specially designed to connect two computers together. Ethernet cables are
physically manufactured in two basic forms, solid and standard. Solid Ethernet
cables tend to offer better performance and protection against electrical
interference. Stranded cables are less prone to physical cracks and breaks
making them more suitable for travelers and portable devices. (21)
Serial
Cable
A serial cable is a cable used to transfer information
between two devices using a serial communication protocol, the form of
connectors depends on particular serial port used. A cable wired for connecting
two DTE’s directly known as null modem cable. The maximum working length of a
cable varies depending on the characteristics of the transmitters and
receivers, the baud rate on the cable, and the capacitance and electrical
impedance of the cable. The RS-232 standard states that a compliant port must
provide defined signal characteristics for a capacitive load of 2,500 pF.
Generally, the RS-232-compatible ports are intended to be connected by at the
most a few tens of metres of cable. Other serial communications standards are
better adapted to drive hundreds or thousands of metres of cable. This cable
has short transmission distance because of noise limiting the transmission of
high numbers of bits per second when the cable is more than 15 metres long.
(22)
Parallel
Cable
A
parallel cable is used to connect to the parallel ports on a computer and a
peripheral device like a printer or external drive. Parallel cables and the
ports to which they connect are slowly becoming obsolete. Much of the purpose
between connecting devices with them have been replaced by USB ports and
storage devices. (23)
Firewire
FireWire is Apple Computer's version of a standard, IEEE
1394, High Performance Serial Bus, for connecting devices to your personal
computer. FireWire provides a single plug-and-socket connection on which up to
63 devices can be attached with data transfer speeds up to 400 Mbps (megabites
per second). The firewire and other IEEE 1394 implementations provide a simple
common plug-in serial connector on the back of your computer and on many
different types of peripheral devices, a thin serial cable rather than the
thicker parallel cable you now use to your printer, for example, a very
high-speed rate of data transfer that will accommodate multimedia applications
(100 and 200 megabits per second today; with much higher rates later), hot-plug
and plug and play capability without disrupting your computer and finally the
ability to chain devices together in a number of different ways without
terminators or complicated set-up requirements. (24)
Processor
(inc. ALU, CU, registers, heat sync and cooling)
The processor is also know as the Central Processing Unit
(CPU) and is considered to be the brain on the computer. In terms of computing
power, the CPU is the most important element of the computing system. The CPU
socket is the connector that interfaces between the motherboard and the
processor. The CPU executes a program, which is a sequence of stored
instructions, each processors has these set of instructions. It executes the programs
by processing each piece of data as directed by the program and the instruction
set. The instructions are stored in a special memory called cache. (12)
ALU The
ALU (Arithmetic Logic Unit) is the part of a computer that performs all
arithmetic computations, such as addition and multiplication. The ALU is one
component of the CPU. (13)
CU The
CU (Control Unit) is the component of the CPU that implements the
microprocessor instruction set. It extracts memory and decodes and executes
them, and sends the necessary signals to the ALU to perform the operation
needed. They are either hardwired, or micro-programmed. (14)
Register
The
register is a high-speed storage area within the CPU. It receives all the data
before it can be processed, for example, if two numbers are multiplied, both
numbers must be in registers, so the result is also place in a register. The
register can contain the address of a memory location, where the data is
stored, rather than just the data itself. The number of registers that a CPU
has and the size of each (number of bits) help determine the power and speed of
the CPU. (15)
Heat
sync and cooling The heat sink is connected to the processor
chip and has a large surface area as it has lots of fins, enabling the heat
transfer to be maximised. It draws heat from the processor, therefore keeping
the temperature down. The processor cooling fan is attached to the processor
chip or the heat sink to prevent it from overheating.
Busses
(inc. control, address and data bus)
A bus is a collection of wires, through which data is
transmitted from one part of a computer to another. In a personal computer, the
bus is also referred as an internal bus, which connects all the internal
computer components to the CPU and the main memory. All busses consist of two
parts:
An
address bus An address bus transfers information about
where data should go.
A
data bus Whereas, a data bus transfers actual data. (16)
A
control bus A control bus is the physical connection that
carries control information between the CPU and other devices within the
computer. (17)
External
Storage
External storage is addressable data storage that is not
currently in the computers main storage or memory. It is also known as
auxiliary storage or secondary storage. (18)
Peripherals
(e.g. digital camera)
Input/output (I/O) ports on a computer connect peripheral
devices such as printers, scanners, and portable devices. The following ports
and cables are commonly used:
·
Serial – either a DB-9 or DB-25 male
connector. It transmits one bit of data at a time.
·
USB – a standard interface that connects
peripheral devices to a computer.
·
FireWire – a high-speed, hot-swappable
interface that connects peripheral devices to a computer.
·
Parallel – a standard Type A DB-25 female
connector.
·
SCSI – can transmit parallel data rates in
excess of 320 MBps and can support up to 15 devices.
·
Network – also known as a RJ-45 port,
connects a computer to a network.
·
PS/2 – connects a keyboard or mouse to a
computer.
·
Audio – connects audio devices to the
computer, such as line in, microphone, line out, Sony/Philips Digital Interface
Format (S/PDIF), TosLink, Gameport/MIDI.
·
Video – connects a monitor cable to a
computer. (19)
Bibliography
(25) Authors:
Karen Anderson, Alan Jarvis, Allen Kaye, Jenny Lawson, Richard McGill, Jenny
Phillips and Andrew Smith – Title:
Information Technology Level 3 Book 1 BTEC National – Publishing location: Pearson Education Limited, Edinburgh Gate,
Harlow, Essex, CM20 2JE – Publisher: Pearson
Education Limited – Date: 2010
