1. Chapter 2 Computer Hardware
This lesson covers:
Personal Computers and their Systems
Mobile computers
Laptops, tablets, smartphone
Hardware and software components
Information about buying computers and system components
Information about troubleshooting a system
Chapter 2 Computer Hardware

2. Components of a personal computer
Motherboard (system board)
Slot for processor
Fan and connector to processor
Slots for main memory (DRAM)
Volatile (data is lost if power is off)
BIOS typically in (flash) ROM memory
Clock generator
Power connectors
Interface to buses for i/o devices
Chapter 2 Computer Hardware

3. Chapter 2 Computer Hardware
System unit
System unit houses
main circuit board
other storage devices (hard disk, optical disk drives, etc.)
typically contains modem, graphics card, sound card, and network interface card (NIC)
Probably wired and wireless NICs (adaptors)
may also contain antenna and speakers
Chapter 2 Computer Hardware

4. Chapter 2 Computer Hardware
Sound system
Output device for digitally represented sound (music, speech, sound effects for system purposes, such as starting up, mail messages, errors)
Sound card sends signals to speakers that may be external or built into the system unit
Chapter 2 Computer Hardware

5. Chapter 2 Computer Hardware
Display system
Visual output
Graphics card converts digital data (such as documents, photos, and videos) to images for display devices (such as monitors, screens)
Chapter 2 Computer Hardware

6. Network and Internet Access
Adaptor is typically inside the System Unit- connects with a cable to a modem and then is then connected to a Router for connection to a LAN and/or the Internet
In most wireless networks, modems connect to an Access Point that then connects to other cells or to a Router
Peer-to-peer wireless networks connect to each other
Chapter 2 Computer Hardware

7. Buying a desktop computer
Desktop computers do not run on batteries
Must be plugged into an electrical output
Price ranges from about $300- $1000
Apple computers are closer to $
Components stored in towers- vertical system units for ease of modification or in screen case
Chapter 2 Computer Hardware

8. Desktop and Portable Computers
The term form factor refers to the size and dimensions of a component, such as a system board or system unit
A desktop computer fits on a desk and runs on power from an electrical wall outlet
Chapter 2: Computer Hardware

9. Portable & mobile computers
Run on electrical power or batteries (as long as battery is sufficiently charged)
Mobility is a great advantage!!!
Smaller, lighter than desk tops
Classified as
Laptops (notebooks)
Netbooks
Tablet PCs
Chapter 2 Computer Hardware

10. Chapter 2 Computer Hardware
Laptops (notebooks)
Lightweight, portable personal computer
Prices range from $400 to $4000 and more
Weigh about 5 or 6 pounds
Mobility
Require assignment of frequency bands (typically by base station)
Most include Bluetooth and/or (also called WiFi), and cameras and speakers
Display is not as good as desktops but uses less power
Chapter 2 Computer Hardware

11. Chapter 2 Computer Hardware
Netbook
(mini laptops)
About 2 pounds and perhaps 7” - 8” wide
CD or DVD drive is connected externally through a serial port
Cost may be less than $300
Bluetooth is typically provided at an extra cost
is included
Chapter 2 Computer Hardware

12. Chapter 2 Computer Hardware
Tablet Computers
Excellent portability
More desirable input capabilities
Touch-sensitive screen
Writing or drawing pad
Keyboard must be attached externally
Some accept voice input
iPad costs about $300 to $1000
Designed for music, video, camera, apps
Chapter 2 Computer Hardware

13. Chapter 2 Computer Hardware
SmartPhones
Convergence of technologies
Mobility, light to carry, power saving capabilities
Camera, video, mail, connection to Internet
Apps
Telephony
Extensive computing, storage via the cloud
Chapter 2 Computer Hardware

14. Software & Hardware Components
Operating Systems
Control hardware devices
Provide user with friendly interface
Manage application programs
Provide protection and security services
Applications Programs
Chapter 2 Computer Hardware

15. Chapter 2 Computer Hardware
Operating systems
As the size of memory in portable computers has increased, the same operating systems as desk tops are being used: typically Windows, Mac, Linux
Android is built on top of a Linux kernel
Chapter 2 Computer Hardware

16. Chapter 2 Computer Hardware
Home Computer Systems
Netbooks, desktops, etc. may be networked together
Used for personal finances (e.g., taxes) and entertainment, photoshop, word processing, digital cameras, downloading music, games, movies)
Internet applications ( , facebook, e-commerce, etc.)
Chapter 2 Computer Hardware

17. Chapter 2 Computer Hardware
Gaming PCs
High end desk top computers
More memory
Better sound
Digitizing analog sound uses more samples
Better video
Digitizing analog pictures takes more samples
Higher resolution
More processing units
Multiple cores
Chapter 2 Computer Hardware

18. Gamer Paladin E810 http://www.ibuypower.com/Info/chimera4se.aspx
Chimera 4 E-1 $979 and up (not top of the line)
• Intel® Core i5-4670k Processor(quad core)
8GB or 32GB of memory
120 mm Liquid CPU Cooling
• 8GB DDR Memory ( DRAM)
• 1TB SATA-III Hard Drive
• Gigabyte GA-X87 HD3 Motherboard
Windows 8
Tower
Chapter 2 Computer Hardware

19. Small business systems
Desk tops typically considered more reliable, less likely to be stolen (or lost), easier to repair
Typically do not have expensive graphics cards, audio systems, perhaps not even speakers
Do have business software
Database, spreadsheets, accounting, etc.
Connection to Internet may be filtered
Employee smartphones may be connected
Security issues
Chapter 2 Computer Hardware

20. Chapter 2 Computer Hardware
What should you buy?
Research the topic! Set a budget!
My opinion is that even the cheapest computers today have more than adequate speed, main memory and hard disk storage for most usage
Check Consumers Report or the Internet for reliability
If you want specific peripherals or software, make sure the computer you buy is compatible
Apple has great graphics for video editing, etc.
Chapter 2 Computer Hardware

21. Chapter 2 Computer Hardware
Compatibility
You want your programs from school or work to be compatible with your home computers
Windows OS today typically runs on Apple computers. Linux OS typically can be installed on Windows and Apple platforms
Check on this before you buy your computer
You want to be able to run Windows applications, particularly your old programs
Chapter 2 Computer Hardware

22. Chapter 2 Computer Hardware
Purchasing software
Most PCs have an operating system and a browser installed
Other software (for example, virus scanning) may be free for limited period
Typically you will have to install software for word processing, spreadsheet, Internet security (although Windows and Apple have their own security programs installed)
Chapter 2 Computer Hardware

23. Chapter 2 Computer Hardware
Upgrading your system
Easy to add external components-
Perhaps plug into the serial (USB) port –
You’ll need a cable (like a printer cable)
External hard drive ($100), mouse ($15 - $50 for wireless), keyboard, add second display screen ($100 or more), new speakers ($100 or more)
Chapter 2 Computer Hardware

24. Chapter 2 Computer Hardware
Upgrading your system
Internal – more difficult; takes longer
Replace mother board (may not pay)
Replace processor (may not pay)
Add memory
Replace graphics card
Replace CD or DVD drive
Chapter 2 Computer Hardware

25. “Modders” custom alter their computers
Add lights, see through cases, paint machines, add components as any hobbyist might
Parts available at Radio Shack and on line
Chapter 2 Computer Hardware

26. Chapter 2 Computer Hardware
Other issues
Warrantee
How long; how much does it cost?
Technical Support
Free? how long does it last? Is the staff any good (go to the Internet for this)
Repairs
Where are the repairs made- are shipping costs covered? What is the turnaround time?
Chapter 2 Computer Hardware

27. Chapter 2 Computer Hardware
Computer Performance
(micro) processor specifications
3.33 GHz indicates speed of processor clock
Clock sets pace for instruction execution
Megahertz (MHz) or Gigahertz (GHz) specifies the number of cycles per second, which affect the number of instructions that can be executed
some instructions need multiple cycles
Pipelined architecture may enable multiple instructions to be executed in a smaller number of cycles
Generally more cycles means more instructions/sec
Chapter 2 Computer Hardware

28. Chapter 2 Computer Hardware
FSB
FSB or front side bus
A bus is a set of wires and circuitry that carry data, addresses, and control information between processor & memory and devices
1333 MHz FSB is a pretty fast bus by today’s standard
Processor and memory continually pass data between each other – bus speed is crucial
Chapter 2 Computer Hardware

29. Chapter 2 Computer Hardware
Words
Word size is the number of bits that the processor works on at a time (size of internal registers), possibly also the number of bits transferred to or from memory at a time
Typically 32-bit or 64-bit architectures are used today
Chapter 2 Computer Hardware

30. Chapter 2 Computer Hardware
Cache
Cache is a high-speed memory
RAM cache, cache memory, CPU cache or internal cache are all terms for the cache that is between the processor and main memory
More expensive, faster, but smaller than main memory
Typically in the Mbytes today
L1 cache is inside the processor; L2 cache is external - between processor and memory
Chapter 2 Computer Hardware

31. RISC and CISC instruction sets
CISC architecture uses many, variable size, powerful instructions
RISC architecture uses a small set of fixed size, comparatively simple instructions
Intel and AMD use CISC architecture
Important issue to consider when told an execution rate of instructions/second
Chapter 2 Computer Hardware

32. Specialized graphics instructions
MMX, AVX, SSE5 are enhanced instruction sets (only for CISC architecture)
Easier for graphics programmer
Typically speeds up graphics and video applications, but only for software that is designed to use these instructions
Chapter 2 Computer Hardware

33. Serial, parallel and pipelined processing
You bake a pizza pie in your oven. After it is finished, you decide to bake another. The pies are baked serially.
Your two friends bake pies in their own ovens. You three are working in parallel.
You make the dough while one friend shapes and the other bakes the pies in the oven(s). You are pipelining your work.
Chapter 2 Computer Hardware

34. Chapter 2 Computer Hardware
Multi-core processor
Processor contains circuitry for multiple processing units.
OS and software must utilize the multiple cores
With current technology, clock speeds have reached close to their limit
Good for games
1 core can handle sound, another core can do rendering, perhaps a third handles display
Chapter 2 Computer Hardware

35. Evaluating performance
Laboratories run tests (benchmarks) to estimate the speed of a microprocessor
AMD (Athlon X2) and Intel (Core 2 quad) have most of the microprocessor market
Intel® Core™2 Quad Processor Q8200 (4M Cache, 2.33 GHz, 1333 MHz)
Advanced Micro Devices
Apple switched from Motorola (RISC) to Intel in 2005
IBM makes RISC processors for servers
Chapter 2 Computer Hardware

36. Chapter 2 Computer Hardware
Random Access Memory
RAM means that it takes the same amount of time to get to any addressable unit
The cache in the system unit is also RAM
Cache is usually denoted as SRAM
Main memory is frequently denoted as SDRAM (Synchronous dynamic RAM)
SDRAM and SRAM are volatile (lose contents if power is turned off)
Chapter 2 Computer Hardware

37. Random Access Memory
Microscopic capacitors hold the bits that represent data
Most RAM is volatile
Requires electrical power to hold data
CLICK TO START
Figure 2-18
Chapter 2: Computer Hardware

38. Compare RAM to hard disk
RAM is smaller and more expensive
RAM is much faster and more reliable
RAM has only electronic units while disks have mechanical parts
CPU works directly with program and data that are stored in main memory
However, because RAM is volatile, anything stored there is lost if power is lost
Chapter 2 Computer Hardware

39. Chapter 2 Computer Hardware
How much RAM do you need?
Check any application before you install it.
Check task manager/performance for amount of free RAM (physical memory)
Most systems running Windows 7 need at least 1 GB of RAM.
Games, video need more memory
Personal computers may have 8GB of RAM
Chapter 2 Computer Hardware

40. Can you run out of memory?
Windows 7, Apple, etc. use part of the hard disk to hold parts of program (divided into pages) that are not currently in use
Called swap area
This “virtual memory” is used by systems to swap different pages between RAM and disk
Large performance degradation occurs when too much page swapping occurs
Chapter 2 Computer Hardware

41. Chapter 2 Computer Hardware
RAM specifications
Today, most RAM stores data in capacitors
SDRAM at 1066MHz is faster than 10 MHz
Measures # of cycles per second
But 10ns RAM is faster than 12ns (12*10-9 sec)
This measures how long one cycle takes
DDR (DDR2, DDR3) means dual-channels
Two channels on the bus to transfer data between processor and memory
Typically installed in a DIMM
(dual inline memory module)
Chapter 2 Computer Hardware

42. Chapter 2 Computer Hardware
question
What does 2GB Dual Channel DDR2 SDRAM at 800 MHz (max 4 GB) mean?
2GB is the amount of bytes in main memory
Dual channel DDR2 specifies two paths to the CPU (faster than 1 channel)
SDRAM is volatile main memory (common)
800 MHz measures RAM speed
You can install up to 4GB more – at most
Chapter 2 Computer Hardware

43. Read-only memory (ROM)
ROM is non-volatile, not changeable
Cannot be written to – more secure
Typically a startup ROM (or variations of ROM) routine is stored in a single integrated circuit plugged into the board to boot system
ROM BIOS (basic input/output system) checks the CD/DVD drive first (at fixed address) to see if it holds a system disk, otherwise goes to hard disk (at known address) to load the Operating System
Chapter 2 Computer Hardware

44. Chapter 2 Computer Hardware
EEPROM
Electrically Erasable Programmable ROM
Configuration information is stored semi-permanently
Not volatile, but must be able to be changed when you add more memory, etc.
You can make changes during setup, if you know what you are doing (F1 while computer is booting)- language, time, date, memory
Get out of Setup with ESC (exit)
Chapter 2 Computer Hardware

45. Chapter 2 Computer Hardware
Storage devices
Data Storage System consists of
Storage device – term used for mechanical unit
Retrieves and writes to the storage medium
Hard disk drives, tape drives, CD and DVD drives, flash drives, external disk drives, SANs
Storage medium – unit that contains data
Disk, tape, CD, DVD, flash memory
Chapter 2 Computer Hardware

46. Chapter 2 Computer Hardware
SSD and HDD
Sold State Drive/ Hard Disk Drive
Secondary storage; Both non-volatile
HDD- Mechanical arm with read/write head
Potential for disk crash
$50 for around 500 GB
SSD all electronic parts
$410 for about 480GB
Possibly less reliable for numerous writes
Chapter 2 Computer Hardware

47. Data representation in storage
Conceptually, two charges stored in capacitors in memory are transmitted as perhaps 2 voltage levels on a bus to a device, where it is stored as perhaps two magnetic or optical states
This is a simplification
Chapter 2 Computer Hardware

48. Factors to consider in choosing storage technology
Cost
Size
Speed
Versatility and portability
Durable (robust)
Direct or sequential access
Data transfer rate
Chapter 2 Computer Hardware

49. Chapter 2 Computer Hardware
Hard disks
Magnetic (bit determined by magnetic orientation of a particle)
Strong magnet can wipe out data
Loses magnetic orientation over time
Mechanical components to read/write data to disk (can have a head crash)
Holds a lot of data in small size unit; fast access; comparatively cheap
Nonvolatile
Chapter 2 Computer Hardware

50. Hard Disk Technology
Hard disk technology is the preferred type of main storage for most personal computers
Not as durable as many other storage technologies
Head crash
Figure 2-25
Chapter 2: Computer Hardware

51. Chapter 2 Computer Hardware
Hard disk metrics
Assume 160 GB 8 ms 7200 RPM HD costs $160
Cost is $1 per gigabyte or 10MB per penny
8 ms refers to access time
the smaller the better
7200 revolutions per minute (RPM)
The faster the better
Specifications may include transfer rate (of perhaps 50MB/s ) dependent on controller
Chapter 2 Computer Hardware

52. Chapter 2 Computer Hardware
Hard disk controller
Technologies for controllers include SATA (Serial Advanced Technology Attachment), Ultra ATA, EIDE, and SCSI
Hard drive manufacturers mount controller circuit on the disk (you don’t have a choice)
Controller communicates with device driver in processor to transfer data, commands, addresses
DMA (UDMA) transfer data directly to memory
Chapter 2 Computer Hardware

53. CD, DVD, and Blu-ray technology
Optical storage
Bits stored as microscopic light (lands) and dark (pits) spots
Light is reflected differently from light or dark colors – interpreted as 0s and 1s
CD – perhaps 700 MB of data; 80 minutes of music
DVD – 4.7 GB (double layer stores 8.5GB)
Blu-ray 25GB per layer
Chapter 2 Computer Hardware

54. Comparing CD, DVD, Blu-ray
Transfer rates of perhaps 64Mbps (CD)
297 Mbps (DVD)
1 layer Blu-ray (36Mbps)
Multi-layered up to 432Mbps
Each uses different data formats for recording different types of data
DRIVERS OFTEN ARE NOT COMPATIBLE
Chapter 2 Computer Hardware

55. Chapter 2 Computer Hardware
Solid State Storage
Flash memory is a popular type
Non-volatile
Electronic (no mechanical parts)
Requires little power
Immune to magnetic interference, temperature fluctuations
Capacity less than hard drives
Tends to “wear out” with use faster than disks do
Chapter 2 Computer Hardware

56. Chapter 2 Computer Hardware
USB flash drive
Solid state; built-in connector to USB port
portable
Vulnerable to viruses
Cheap
Capacity of perhaps up to 64GB
Transfer rate of up to perhaps 28MB/second
Chapter 2 Computer Hardware

57. Storage Wrap-up
Figure 2-34
Chapter 2: Computer Hardware

58. Chapter 2 Computer Hardware
Software for devices
Manufacturers provide software called “device drivers” to communicate with controllers
Windows OS recognizes a number of devices (flash drives, external hard drives) and configures system automatically – called Plug and Play
You may have to load device driver yourself from supplied disk or from the Internet
Always “safely remove hardware” [taskbar]
Chapter 2 Computer Hardware

59. Hardware Security and Maintenance
Do not leave notebook computer unattended
If you leave it in the car, lock it up.
Record tracking information of notebook and store it separately
Use an anti-theft device
STOP plates contain tracking mechanisms
Cables, motion sensor alarms
Chapter 2 Computer Hardware

60. Chapter 2 Computer Hardware
Surge Protection
Always use a surge strip (suppressor)
You frequently have small surges of power in your home – perhaps when the air conditioner goes on
Even small surges can cause gradual damage to computer equipment
Large surges will destroy computers
Unplug surge strip during lighting storm
Chapter 2 Computer Hardware

61. Chapter 2 Computer Hardware
UPS
Provides battery backup in case of power failure
Check on the amount of time (limited)
UPS unit may also include surge protection
Chapter 2 Computer Hardware

62. Chapter 2 Computer Hardware
Basic Maintenance
Clean keyboard (unplug first)
Do not eat or drink while typing
Screen
Clean regularly
Turn it off to see smudges better
Do not scrub
Do not spray cleaning liquid directly on screen
Chapter 2 Computer Hardware

63. Chapter 2 Computer Hardware
Temperature
Keep computer in cool place
Keep area free around computer
Internal fans cool equipment
(graphics equipment particularly sensitive)
You can try to blow air through the equipment, but turn it off first.
Chapter 2 Computer Hardware

64. Chapter 2 Computer Hardware
Software maintenance
Back up files regularly
Run disk cleanup and disk defragmenter
If system does not do so automatically
Delete your browser’s history and cache files
Automatically update OS (patches) and virus protection
Scan your computer for viruses
Chapter 2 Computer Hardware

65. Chapter 2 Computer Hardware
Troubleshooting
First, check all cables
If system hangs, shut if off, count to 20, turn it on again.
Sometimes that works if problems are transient
Run your virus protection
Check the Internet for a similar problem
Chapter 2 Computer Hardware

66. Disposal of computer components
Be sure that all sensitive data is erased.
Write over multiple times
There are programs for this.
Or remove your hard disk before disposing of your computer.
Chapter 2 Computer Hardware

67. Where does e-garbage go?
Discarded computer components generate tons of toxic waste
Cathode-ray tube monitor can contain 8 pounds of lead
Should disposal be taxed?
Might make environmentally friendly components more competitive
Users and manufacturers must cooperate
Chapter 2 Computer Hardware