understanding and assessing hardware

8/3/2019 Understanding and Assessing Hardware

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Understanding and Assessing Hardware

To Buy or to Upgrade?

Things to consider

Moores Law

Cost of upgrading vs. buying

Time to install software and files

Needs and wants

Determine your ideal computer system

Assess existing computers subsystems

CPU


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RAM

Storage devices

Video

Audio

Consider training needs

Desktop of Notebook?

Desktop

Hard to move around

Less expensive

Harder to steal

Easier to expand and upgrade

Difficult to transport

Notebook

Portable

More expensive

Easily stolen

Difficult to upgrade


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Easy external expansion

Prone to damage

To Buy or not to Buy


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How Does the CPU Work?

Control unit

Arithmetic logic unit (ALU)

Machine cycle

Fetch

Decode

Execute

Store


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Machine Clocks

The timing of each cycle is defined by the system clock

The clock cycle sets the pace and this pace is known as the

clock speed

Measured in Hertz (Hz) or number of times per second

3 GHz = 3 billion times per second

Differentiating CPUs

Processing power

Core: a complete processing section from a CPU embedded

into the same physical chip

Clock speed

Cache: the amount of immediate access memory the CPU has

Front side bus: connects the processor to system memory

(RAM)


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Hyperthreading: allows one instruction to be begun before the

previous one is finished

Evaluating the CPU

Identify your current CPU

Determine whether it is meeting your needs

Go to Task Manager to review your CPU usage

Consider how quickly data moves to or from the CPU

Evaluating RAM

Random access memory (RAM)

Temporary storage (memory)

Volatile

Memory modules fit on motherboard


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Most are called dual inline memory modules (DIMMs)

DDR2

DDR3

SRAM

DRAM

SDRAM

How Much RAM do you Need?

Physical memory vs. kernel memory

Need RAM for operating system, application, software, and data

Virtual Memory

Memory-bound system

Virtual memory

Page file (Swap)

Drawback = speed

Increasing RAM can avoid this

problem

Adding RAM


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Things to consider

Type of RAM module

Amount of RAM

Maximum limit

Number of slots

Operating system

Relatively easy to add by yourself

Watch prices carefully lots of fluctuation

Storage (permanent)

Types of storage (devices)

Hard drive

USB flash drive

Optical drive

External hard drive

Online storage

Nonvolatile storage

The Hard Drive

Storage capacity is up to 2 terabytes (TB)


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Stack of typewritten pages over 100 miles high

Access time is measured in milliseconds

Data transfer rate is measured in megabits or megabytes per

second

How a Hard Disk Works


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Composed of coated platters stacked on a spindle

Data saved to the disk: pattern of magnetized spots

Spots = 1

Spaces = 0

Spots are translated into data

Divided into tracks and sectors

Arms pass between the platters (which spin at up to 15,000RPM)

Read/write head is attached to end of arm

Access time is the time taken to locate the data on the platter and

send it to RAM

Evaluating Storage

Identify your hard drives total capacity

Determine your storage capacity needs

Music and photos 30-100GB

Videos 100-200 GB (more if all HD)

Consider data transfer rates

Internal

External

SSD or ATA?


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Optical Storage

Optical media: store data as tiny pits burned into a disc by a laser

Prerecorded

CD-ROM, DVD-ROM, BD-Rom

Recordable

CD-R, DVD-R, BD-R

Rewritable

CD-RQ, DVD-RW, BD-RE

Consider replacing CD/DVD drive with BD burner


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Different DVD formats

DVD-R or DVD-RW (dash)

DVD+R or DVD+RW (plus)

DVD-RAM (encased in plastic)

Need to know the format of your drive and buy the appropriate

media

How does it work?


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ROM: bumps in the mirror put there when manufactured.

Therefore cannot be changed.

R: A clear dye covers the mirror. The write laser heats the

dye to make it opaque. Reads the difference between opaque

and reflective.

RW: Special dye layer that can be changed at a certain

temperatures to vary between clear and opaque.

Blue-ray:

Shorter wavelength

Pits on top of disc

Stops birefringence disc tilt

Needs extra layer for protection


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Speed of drives

CD-RW 52x32x52

Records at 52x150 Kb/s

Re-writes at 32x150 Kb/s

Playback at 52x150 Kb/s

1xDVD approx. 1.3 Mb/s

1xBD approx. 36 Mb/s


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Evaluating Video

Two components

Video card (adapter)

Monitor

Video Cards

Process binary data into images

Contain memory known as video memory

Control the number of colours a monitor can display (bit depth)

Standard VGA

True colour


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Graphics Processing Unit

Performs the same work as a CPU

Specialized to handle

3D graphics

image and video processing

CPUs perform better with a GPU handling graphics computation

Evaluating Video

Identify the amount of video memory on your video card

Determine your video needs

128 MB is a realistic minimum

Consider how many monitors you want to use

Bit Depth: the number of bits used to describe the colour of a

single pixel.

4 bit gives 16 colours, the minimum for colour monitor

Most video cards now come in 24 bit, giving 3x8 bit

descriptors, one each for red, green, and blue

Each colour has 256 shades

256x256x256 = 16,777,216 colour possibilities

True colour


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Evaluating Audio

Sound cards

Attach to motherboard

Process digital data into sounds

3D sound cards

Surround sound

Allow you to connect audio devices

Evaluating System Reliability

Performance problems

Slow

Freezes

Crashes


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Upkeep and maintenance

System tools

Control Panel

Update software

Clean out your startup folder

Clear out unnecessary files

Run spyware/adware program

Run the Disk Defragmenter utility

Update Software and Hardware Drivers

Software

Patches

Automatic updates

Hardware

Download updated drivers

The Last Resort

If problems persist:

Upgrade the operating system to latest version

Reinstall the operating system


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The Final Decision

How closely does your system meet your needs?

How much would it cost to upgrade your system?

How much would it cost to purchase a new system?

understanding and assessing hardware

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