Computer Hardware
Technologies that enable a computer to store and retrieve
data and programs
Objectives
•Introduce
Storage Technology
•Compare
Storage Technologies
•Compare
Storage Media and Devices
•Explore
Floppy Disk Technology
•Explore
CD/DVD Technology
•Understand
Expansion Slots, Cards, Ports, and Cables
•Compare
Display Devices
•Compare
Printers
•Examine
Keyboards
•Explore
Peripheral Devices
Storage
•Storage
Medium: (the item)
–Disk,
–CD,
–DVD,
–Paper,
etc
•Storage
Device: ( the mechanical)
–disk
drives,
•Floppy drives
•CD drives
•Hard drives
Data Storage Process
•Data
is copied into RAM because the computer will operating
faster by retrieving the data from this location rather than from any other
storage location.
•RAM
data is temporary, it is replaced with the new data
that you are working on.
Magnetic Storage
•Magnetizes
particles on the surface
•Permanent,
but modifiable
•Hard
disk, floppy disk, zip disk and tape
•Read-write
head
•Not
very durable, can be destroyed by magnets
Optical Storage
•Stores
data as light and dark spots on the disk surface.
•Called,
Pits and lands
Comparing Storage Devices
•Versatility
•Durability
•Speed
–Speed
is the Access time and the data transfer rate
•Capacity
is measured in
–Kilobytes kB,
–Megabytes
MB,
–Gigabytes GB,
–Terabytes TB
Comparing Storage Devices
Adding Storage Devices
•Upgrading
your computer
•Your
computer contains unused drive bays
Floppy Disks are Portable
Hard Disks (Fixed Disks)
•One
or more platters with read/write heads
•Capacity
averages 40 GB
•Very
fast access times (rpm)
•Platters
divided into tracks, sectors, cylinder
•Controller
(circuit board)
–Ultra AT
–EIDE
–SCSI
•Head
Crash
RAID
•Redundant
Array of Independent Disks
•Redundant
Array of Inexpensive Disks
•Combines
two or more drives
•Faster
access and protects data from loss
•Mainframes
and servers
CD Technology
•CD-ROM:
Compact Disk Read-Only Memory
–Manufactured;
cannot change; 680 MB
•CD-R:
Compact Disk Recordable
–You
record; cannot be erased or modified
•CD-RW:
Compact Disk Rewritable
–You
record; can erase and rewrite
DVD Technology
•Digital
Video Disk
•Originally
alternative to VCR
•4.7
GB
•Can
play CD-ROM and most CD-Rs and CD-RWs
•Manufacture
permanently stamped the DVD so you can not change it.
Busses
•Data
Bus: circuits on which data travels within the computer
–Between
RAM and CPU
–Between
RAM and storage devices
•Expansion
Bus
–Part
of data bus between RAM and the peripherals
Expansion Slots and Cards
•Cards
also called expansion boards, controller cards, adapters
•Desktops
have 4 to 8 slots
•Standard
cards
–Graphics
or video card
–Modem
card
–Sound
card
–Network
card
Expansion Slot Types
•ISA:
Industry Standard Architecture
–Older;
modems and slow devices
•PCI:
Peripheral Component Interconnect
–Fast;
graphics, sound, video
•AGP:
Accelerated
–Fast;
graphics
PCMCIA (PC Card)
•Personal
Computer Memory Card International Association
•Found
on notebook computers
•Type
I, II, III
Expansion Ports
•Jacks
or connectors
•Mouse,
keyboard, serial, USB
•Cables
Display Devices
•Graphics
card
–Video memory
–AGP expansion card
–Accelerator technology
•CRT:
Cathode Ray Tube
–Inexpensive and dependable
•LCD:
Liquid Crystal Display
–Expensive; found on notebooks
–Limited viewing angles
–Active Matrix or TFT (thin film
transistor)
Display Device Image Quality
•Screen
size (13” to 21”)
•Dot
pitch
–Distance
between like-colored pixels
–.26
or .23 typical (smaller is better)
•Resolution
–Horizontal
and vertical pixels on screen
–640
x 480, 800 x 600 and 1024 x 768
•Color
or Bit Depth
–Number
of colors that can be displayed
–24-bit
(true color) = millions of colors
Printer Comparison Criteria
Printer Types
•Ink
Jet printer
•Solid
Ink printer
•Thermal
Transfer printer
•Dye
Sublimation printer
•Laser
printer
•Dot
Matrix printer
Ink Jet Printer
•Nozzle-like
print head sprays ink
•Low
cost
•Can
smudge
•Color;
black and white
Solid Ink Printer
•Crayon-like
ink is melted and sprayed
•Vibrant
colors on most types of paper
Thermal Transfer Printer
•Uses
wax that is melted
•Needs
special paper/transparencies
•Expensive
Dye Sublimation Printer
•Like
wax transfer, but uses heated dye
•Need
special paper
•Excellent
color quality
•Expensive
Laser Printer
•Same
technology as photocopier
•Fax
•High
quality
•Fast
Keyboards
Peripherals
•Device
driver software on CD
•Plug
and Play (PnP)
TechTalk: Windows Registry
•Registry
is the glue that binds together the PC hardware, peripherals, application and
system software
•Operating
system needs to know (and registry holds)
–where
peripherals are located
–what
has been installed
–how
they are configured
–how
you want to use them
Techtalk: continued
•Examples:
resolution, shortcuts, system events, network settings, uninstall routines
•System.dat and User.dat
•Registry
updated when you install or remove hardware or software
Issue
Computer Hardware
End