1. Using System Software
Chapter 5

2. Announcements Chapter 6 Homework is posted
Windows 7 Quiz Homework is removed
Chapter 5 Homework should be complete
Windows 7 Simulator Homework should be complete

3. Objectives Upgrade vs. Buy Evaluating your system System Reliability
CPU
RAM
Storage Devices
Video Card
Sound Card
System Reliability

4. To Buy or Upgrade Things to Consider Moore’s Law
Cost of Upgrade vs. Buy
Time to install software / restore data
Needs vs. Wants

5. To Buy or Upgrade Determine your ideal computer system
Assess existing computer’s subsystems
CPU
RAM
Storage Devices
Video
Audio
Consider training needs

6. Desktop vs. Notebook Desktop Notebook Hard to move Portable
Less expensive
Harder to steal
Easier to upgrade
More upgrade options
Larger monitors
More powerful
Portable
More expensive
Easily stolen
Difficult/Limited upgrades
Prone to damage
Smaller display

7. How a computer works

8. How a computer works

9. How Does the CPU Work? Control Unit Arithmetic Logic Unit (ALU)
Cache (Pron. “cash”)
Machine Instruction Cycle
Fetch
Decode
Execute
Store

10. Single Core CPU Diagram

11. Dual Core CPU Diagram

12. Control Unit Coordinates all the activities of the CPU
Responsible for the effective speed of a CPU
Contains the “Clock”
Clock speed is measured in cycles per second, or Hertz.
1 Hertz (Hz) is equivalent to 1 cycle per second
1 cycle is roughly equivalent to 1 instruction per second
Responsible for coordinating the machine instruction cycle

13. Arithmetic Logic Unit (ALU)
Responsible for performing arithmetic functions
Example:
Add, Subtract, Multiply, Divide
Performs logical functions as well
And, Or, Not, Xor

14. Cache
Special memory reserved for storing frequently accessed data/instructions
Divided into levels
L1 – Closest to CPU core. Extremely fast
L2 – Further from CPU core, shared between multiple cores.
L3 – Furthest from CPU, also larger and can hold more information

15. CPU Register
Contains the current data being used by the current instruction
Fastest possible data access for the CPU, nearly instant
All instructions and the data they need to work on are copied into a register while being processed

16. Machine Instruction Cycle
1. Fetch
2. Decode
3. Execute
4. Store

17. Machine Instruction Cycle
Fetch: Gets the next instruction to be processed
Decode: Figures out what that instruction wants to do
Execute (Optional): Performs whatever actions instruction demands
Store (Optional): If there is a result of an arithmetic operation, that result should be saved
From the moment the machine is turned on, to the moment is turned off, the CPU is looping through these four modes.

18. Storage
RAM
Cache
Register
CPU
Memory Access

19. Hyperthreading Allows a single core to simulate multiple cores
Appears to the system as if there are actually two cores present
Any time the CPU is idle (waiting on data from a disk or memory for example), it can instead be given another task to do
This makes it appear that two different programs are being processed at the same time

20. Differentiating CPUs Processing power:
Core: A complete processing unit (Control Unit, ALU)
Multi-Core: Multiple cores contained in the same chip
Clock speed: How quickly the processor works
Cache: The amount of immediate access memory the CPU has
Front side bus: Connects the processor to system memory

21. Evaluating the CPU Identify your current CPU
System properties, original documentation, manufacturer’s website
Determine whether it is meeting your needs
During “normal use”, go to task manager and review CPU usage
If over 90%, consider new CPU
A CPU upgrade for the average person is rarely necessary

22. Random Access Memory (RAM)
The type of memory module needed is determined by the motherboard
Factors to consider
Operating System
Type
Speed
Maximum Capacity
Number of Modules
Timings (Advanced)

23. RAM: Types Most RAM today is “Dual Inline Memory Modules” (DIMM)
Uncommon:
SRAM – Static RAM (Not used in RAM anymore)
DRAM – Dynamic RAM
SDRAM – Sychronous Dynamic RAM
Common:
DDR2 SDRAM
DDR3 SDRAM
Laptops use:
SO-DIMM DDR

24. RAM: Speed Measured using two scales
Clock Speed / Data Rate: Measured in millions of transfers per second
How many millions of pieces of information can be transferred in a second
Example: DDR3-800 or DDR3-2133
Peak Transfer Rate: Measured in millions of bytes per second
How many millions of bytes can be transferred in a second
Example: PC or PC
Speed should match the specifications for the motherboard

25. RAM: Capacity / Size
Motherboards will specify the maximum size per module.
Typically: 1GB, 2GB, 4GB
A motherboard also has a finite number of slots available to place memory. Usually a multiple of 2.
Typically: 2, 4, 6 or 8 slots
It is recommended to upgrade memory in pairs. That is, buy 2 modules that are identical to the existing modules. Do not mix & match. Do not buy just one (some MBs do not allow odd numbers of modules)

26. RAM: Timings (Advanced)
Accessing RAM is much slower than a single instruction cycle.
In some cases, a CPU can perform thousands of operations in the same time it takes to retrieve one piece of information from RAM
Timings refer to how fast data can be read and written
Measured in clock cycles for SDRAM, nanoseconds for DRAM
Example: 5-5-5
5 clock cycles between asking for data and beginning to recieve it

27. How much RAM do you need?
RAM is used for both the OS and all currently running applications
Should aim to never use more than 50% of available memory on average
Application
Recommended RAM
Windows 7
2,048 MB (2GB)
Office 2010
512 MB
Internet Explorer
iTunes
1,024 MB (1GB)
Total:
4096 GB

28. How much RAM do you need? Operating System
Due to the limitations of 32-bit systems, memory over 4GB is not used. Upgrading a 32-bit OS beyond 4GB will have no effect.

29. Storage Nonvolatile storage Types of storage devices
Persists when computer is turned off
Types of storage devices
Hard drive
USB flash drive
Optical drive (CD/DVD/Bluray)

30. How a Hard Drive works
Composed of coated platters stacked on a spindle
Data (0’s and 1’s) saved to the disk in a pattern of magnetized locations
Read/write head and platters combine movements to access all areas of the platter.

31. Hard Drive (HDD) Things to consider Type Interface type Size
RPM (rotations per minute)
Access & Seek time
Data transfer rate

32. HDD Type Traditional Hard Disk vs. Solid State Disk Traditional
Much higher storage capacity
Very cheap $ to GB ratio
Solid State Disk (SSD)
Very expensive (nearly $1/GB)
Lower storage capacity (for now)
Extremely fast
Durable (no moving parts)

33. Interface Type ATA – Asynchronous Transfer Attachment
SATA – Serial Asynchronous Transfer Attachment
SCSI – Small Computer Serial Interface
Most common – SATA

34. Size
Windows limits by default a single storage disk to 2TB (Terabytes)
Hard drives currently reach 4TB of storage space and growing
Your book states 2TB is the max, it is not.

35. Rotations Per Minute (RPM)
Measures how fast the disk can spin
Helps determine access and seek times
SSD: Does not rotate
RPM
Seek Time
15,000
2ms
10,000
3ms
7,200
4.1ms
5,400
5.6ms
4,800
6.3ms

36. Access & Seek Time Measured in milliseconds Seek Time Access Time
Measures how long it takes to locate the requested data on the hard drive
Averages roughly 3-5ms for good drives
SSD: No seek time!
Access Time
Measures how long it takes for a drive to retrieve a piece of information
Averages roughly 9-12ms (less than 9 is good)
SSD: Roughly 100 microseconds (0.1ms, 900x faster than HDD)

37. Data Transfer Rate
Measures, in bytes, how fast data can be transferred per second.
Manufacturers report the theoretical maximum speed under ideal conditions
Good HDD are between 80 and 100+MB/s
SSD: Average MB/s up to several GB/s

38. Evaluating Storage Identify your hard drive’s total capacity
Determine your current storage usage / needs.
More flexibility with HDD choices when upgrading
HDD choice is limited only by connector type for the motherboard
Nearly all consumer computers these days use SATA
You choose speed and capacity based on budget

39. Optical Storage Optical media (read/written by laser)
Pre-recorded media
CD-ROM, DVD-ROM, BD-ROM
Recordable media
CD-R, DVD-R, BD-R
Rewritable (write many times) media
CD-RW, DVD-RW, BD-RE
Very rarely upgrade optical storage. Most common device: DVD-RW

40. Video Two components Factors to consider Video Card Display
Computer Usage: Video Games vs. Traditional Productivity
Display input connection
Number of displays

41. How does a video card work?
Converts binary data into an image
Contains special hardware to convert 3 dimensional information into an image very, very quickly
Contains special memory designed to work with the video hardware
While a CPU core does only 1 instruction at a time, a GPU can do millions of instructions at the same time
Also called a Graphics Processing Unit (GPU)

42. Graphics Processing Unit
Works side-by-side with the CPU to control video output
Two primary manufacturers: NVidia, AMD (ATI)
Will provide minor improvements to productivity display, especially on Windows 8.
Is not necessary for day to day average computer usage
Essential to video games. Most modern games require an expensive video card and will not function without one.
Book correction: The GPU does *not* perform the same computational work that CPU performs. GPUs work in a very special way to convert 3D data into a 2D image to display on your monitor.

43. Evaluating Video Decide if you want to play modern video games
Simple games such as Facebook games and other browser based games do not require expensive video cards
Decide if you want to support multiple monitors
Most video cards will support up to 2 monitors
Determine your budget
Video card prices range from $50 to $800. The price of the card more-or-less relates to the types of games you want to play.

44. Evaluating Audio Sound cards convert digital data into sound
Most every computer system supports at least 2 stereo speakers
Most computer post-2007 supports 5.1 or 7.1 surround sound
A sound card will not improve system performance. Sound cards today are mostly used for audio professionals such as music studios and audiophiles.
Rule of thumb: If you can hear the difference, and it bothers you, between a CD recording and an MP3 player, you might consider an advanced sound card.

45. Evaluating System Reliability
Performance Problems
Slow
Freezes
Crashes
Upkeep and maintenance
System tools
Control panel
Update software

46. Upkeep and Maintenance
How to speed up your computer
Remove unnecessary programs from startup folder
Delete unnecessary files
Run spyware and adware removal programs
Run disk defragmenter (rarely)

47. Update Software Software updates improve reliability and security
Make certain you are running Windows Updates
Update Flash and Java

48. The Last Resort Reinstall OS The decision is based on cost vs. time
All problems on a computer can technically be solved given enough time and the right technician, but can you wait?
Remember, time = money!

49. The New Computer Effect
Beware the new computer effect!
A new computer at home or at work can artificially influence your perceptions
Use the diagnostic tools at your disposal to determine if you really do require an upgrade before spending the money

50. The Upgrade Bottom Line
Audio, Optical, and CPU upgrades are extremely rare today. Most of these are “Upgraded” only when a new system is purchased.
Increasing storage capacity will not improve system performance unless you have reached capacity.
RAM is the most cost effective way to improve performance
A new video card can significantly improve gaming performance, even in older systems