CT10404E PC Technology

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CT10404EPC Technology

• Week 4Specifying and buying a PC

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Whats in store this week

• (Brief) Review of Week 3
• Specifying a PC
• Needs Analysis
• Prioritising
• Shopping around
• Example

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(Brief) Review of Week 3

• Memory
• Hard Disks
• Expansion cards
• Graphics cards

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Specifying a PC

• In the past weeks we have looked at some of the
  components that make up a PC.
• Many companies will sell you assembled PCs
• Alternatively you can build your own from
  components
• At your own risk!

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Specifying a PC - Needs Analysis

• The first thing to do before buying a PC is to
  analyse your needs.
• What will be the uses for your PC?
• 3D animation?
• Image manipulation?
• Word processing/DTP?
• Web browsing?
• Audio processing?
• Games?

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Specifying a PC - Needs Analysis

• What are the requirements for the tasks we wish
  to do?
• 3D Animation
• processor and graphic intensive
• storage space required?
• Memory?
• Image Manipulation
• Memory-intensive
• processor?
• Storage space?

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Specifying a PC - Needs Analysis

• Word processing
• Does this need anything special?
• A big monitor?
• Web browsing
• A fast internet connection, perhaps.
• Anything else?
• Audio processing
• Memory
• Storage space
• Perhaps specialist equipment (professional audio
  I/O?)
• Games
• Everything!

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Specifying a PC - Needs Analysis

• We can break down the specification into the base
  components
• Monitor
• Processor/Motherboard
• Memory
• Graphics Card
• Sound Card
• Other I/O
• Modem, Network Card

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Specifying a PC - Needs Analysis

• Hard Disk
• Interface
• Removable Media
• CD-Rom, DVD-Rom, CD-RW, Zip, Floppy
• Input devices
• Keyboard, Mouse, Games controllers, Graphics
  tablets
• Software
• Support/warranty

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Specifying a PC - Prioritising

• When buying a PC there will always be a budget.
• If money is no object, then why not get the very
  best of everything?
• It will be necessary to make trade-offs between
  performance and price.
• If the PC is for a private individual, then VAT
  will be payable (at 17.5).
• If buying from abroad, beware of customs charges
  and compatibility.

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Specifying a PC - Prioritising

• The first choice to make is whether to buy a
  branded model or a generic one (or build your
  own)
• A branded model will usually cost more than the
  equivalent specification of generic PC.
• But on the flip side, they often come with
  generous warranties, perhaps including on-site
  repair.
• They also often come with software pre-loaded.

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Specifying a PC - Prioritising

• The choice of a proprietary machine such as
  Apples Macintosh is an option.
• A laptop may be preferable over a desktop
• Laptop has mobility.
• Desktop tends to be significantly cheaper for
  similar specification.
• Desktop tends to have the option of higher-end
  components if needed.

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Specifying a PC - Prioritising

• Whether building your own or buying a ready-made,
  there will be a choice for each component.
• A general rule-of-thumb is that you pay a hefty
  premium to be at the cutting edge of technology.
• The high-end consumer graphics card over the
  period 1998-2002 tended to be 300
• A mid-range card was approximately 80

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Specifying a PC - Prioritising

• Another rule-of-thumb is that whatever you buy
  today will invariably be cheaper tomorrow
• Todays top-end card is next years mid-range.
• The trick is to buy only as much as you need -
  and leave scope for upgrading later.
• By buying a mid-range card this year, then
  upgrading next year you will have spent only 160
  instead of the 300 buying the card new would
  have been.

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Specifying a PC - Prioritising

• It may help to list the components and try to
  rank them in order of importance.
• You could then spend more on the higher-ranked
  components and less on the lesser-ranked ones.
• Some components should be viewed as high priority
  in most cases
• e.g. Monitor (if the computer is intended to be
  used for reasonable periods of time)

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Specifying a PC - Specifying

• Monitor
• Options CRT (Cathode Ray Tube) 14 - 21
• Like a TV
• Consider refresh rate, visible display, type of
  tube (normal, FST, trinitron, diamondtron)
• LCD (Liquid Crystal Display) 15-18
• A truly flat screen
• Consider response time, viewing angle, type of
  display (DSTN or the newer TFT)
• Plasma screen/Projector
• Very large sizes
• Expensive!

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Specifying a PC - Specifying

• Processor/Motherboard
• Number of processors (typically 1 or 2)
• If you have an operating system that supports it
  (Windows 2000, Windows XP, Linux), having
  multiple processors is a cost-effective way of
  increasing performance
• Processor speeds and models
• Typically three tiers of processors
• High-end server (Intel Pentium 4 Xeon)
• High-end consumer (Pentium 4, AMD Athlon)
• Budget consumer (Intel Celeron, AMD Duron)

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Specifying a PC - Specifying

• Motherboard
• Built-in peripherals
• Graphics
• Sound
• Network card/Modem
• Disk adapters (IDE, SCSI, RAID)
• I/O (Serial, Parallel, USB, Firewire)
• Power supply
• If building a powerful machine, youll need a
  power supply unit (PSU) powerful enough to run
  everything.

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Specifying a PC - Specifying

• Memory
• Amount and type
• Almost certainly be dictated by the motherboard.
• Modern machines have DDRRam and Rambus.
• Heavy applications will need lots of Ram.
• Intensive graphics or 3D can use almost as much
  as you can afford to give it.
• Dont go lower than 128MB Ram, in general.
• Windows 98 cannot properly support more than
  512MB of Ram (NT, 2000, XP and Linux can though).

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Specifying a PC - Specifying

• Graphics Card
• Modern cards combine 2D with 3D acceleration.
• Dedicated Video Ram on board.
• May offer accelerated DVD decoding.
• TV Out, Digital Out, multiple monitors.
• Most modern cards can support very high
  resolutions and monitor refresh rates

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Specifying a PC - Specifying

• Sound Card
• Higher-end cards may offer Digital out, multiple
  channels of sound, surround sound, real-time
  digital effects.
• Network Cards, Modems c
• For connecting to networks (see next week)
• Modems - speed (in Baud), standards (V90, K56)
• Network cards - speed (in Mbit/s), duplexing

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Specifying a PC - Specifying

• Hard disk
• You pay more for faster access times, more
  storage space, faster data rates.
• SCSI or IDE
• Consider buying multiple smaller drives instead
  of one large drive (and perhaps RAID - Redundant
  Array of Inexpensive Disks)
• Removable Media
• It is almost essential to have a CD-Rom for most
  purposes

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Specifying a PC - Specifying

• Removable Media
• DVD-Rom is the next step forward
• Movies!
• CD-RW to write your own CDs - 650MB of space on a
  single CD
• For a price, you can get a combined CD-RW/DVD
• Zip disk drive?

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Specifying a PC - Specifying

• Input Devices
• Keyboard and mouse are essential
• Ergonomic keyboard
• Optical Mouse
• Trackball
• Gaming controllers (if you are a gamer)
• Arcade stick
• Joypad
• Flight Stick
• Steering Wheel
• Light gun

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Specifying a PC - Specifying

• Software
• The software you need will depend completely on
  what you need to be able to do and what software
  you prefer to use
• Software can often cost more than the hardware
  itself
• Autocad 2002 - 675 inc VAT
• Ensure you leave money for the software! Some
  companies have student licenses
• Autocad 2002 Student - 111 inc VAT

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Specifying a PC - Shopping Around

• Shopping around
• Once you have an approximate specification, its
  time to go shopping.
• Follow commercial practice Look for at least
  three quotes for similar specification. Weigh up
  the pros and cons of each.
• Try online retailers - often sell cheaper than
  high-street companies due to lower running costs
  - Look in Computer Shopper for the web addresses,
  or do a web search

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Example

• Specification for a PC used mainly for
  cutting-edge computer games
• Modern computer games push the boundaries for
  consumer PCs.
• Assume a budget of 1,250.
• Priorities
• High Video Card. Sound Card Processor Gaming
  Controllers Keyboard/Mouse
• Medium Monitor Memory DVD
• Low Hard Disk Modem

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Example

• Video Card GeForce 4 Ti 4600 223.25
• Sound Card Soundblaster 5.1 Digital 52.87
• Processor Athlon XP 2100 164.50
• Motherboard Abit KG7 81.07
• Gaming Controllers Microsoft Sidewinder
  FF 52.87
• Keyboard/Mouse Microsoft Optical
  mouse 17.62 Cherry non-click keyboard 29.37
• Monitor Iiyama 1451 19 186.82
• Memory 256MB DDRRam 51.24
• DVD-Rom Philips 16x 41.12
• Hard Disk Maxtor 20GB IDE 55.22
• Modem 11.75
• Miscellany (Case, FDD) 80.00
• TOTAL 1047.70

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Example

• This computer will still need software.
• Will 102.30 be enough?
• If not, then perhaps we need to go back and
  re-evaluate our choices.

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Practical Work

• A number of specification exercises
• Specifics can be found on the MSG at
• http//mercury.tvu.ac.uk/pct/

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Next Week

• PC Networks and the Internet