CSCI1412 Lecture 13

phones off(please) CSCI1412Lecture 13 Hardware 7 System Specification Dr John Cowell

Overview • System life cycle • determining requirements, sourcing • System specification • costs, PPI (price performance index) • types: desktop, laptop, server / workstation • the main components and factors • Upgrading • processor, memory, hard disks, expansion cards • Maintenance and care • warranties, maintenance, health and safety, care

System Life Cycle

System Life Cycle • Ascertain the user requirements • Determine hardware and software needed • Identify alternative suppliers • Purchase equipment • Install the hardware and software • Train the users • Run the system • optional: upgrade the system • maintain the system

Ascertain User Requirements • This means ‘ask the users what they want’! • find out what they want to actually accomplish • not asking the users what they think they want to buy • typical information to extract • what sort of documents, types of work • letters, reports, memos, etc: word processing • accounts, numerical analysis: spreadsheet • data manipulation, storing, retrieving: database • how many documents, volumes of work • how much sharing of information • networking: LAN, WAN access • budgets, user knowledge, environments, expectations • Do they have any existing IT equipment?

Determine Solution • This means ‘tell the users what they need’! • use your skill and knowledge as the ‘expert’ to specify the hardware and software requirements of the users • the difficulty and skill is in recommending systems that are adequate for the job (for the lifetime), but without costing (wasting) money through over specification • there is no point recommending the latest multimedia, 3D graphics, DVD-RW, 26” Monitor if the user just wants to write one letter per week! • If there was any existing IT equipment, an upgrade may be a good solution • otherwise migration will have to be planned / costed

Selection and Purchasing • Many organisations require three or more quotes • perhaps obtain quotes from three types of sellers • manufacturing company (e.g. IBM) • direct sales (e.g. DELL) • ‘box-shifter’ (e.g. PC World) • When purchasing be careful of: • changing specifications and / or prices • terms and conditions: delivery charges, warranty • There are options on method of purchase • outright purchase • leasing (pay amount each month over e.g. three years) • can be attractive for businesses (servicing often included)

Installation, Training & Maintenance • For most commercial systems installation, training & maintenance should be included in specification • this is expected and companies are prepared to pay for these services • Once installed, system must run for several years • usually at least three years, often five or more • The system should have enough capacity to cope • may need to be upgraded during lifetime • Normally, some consideration will be needed of system reliability and long term maintenance • maintenance / service contracts included in purchase?

System Specification

PC Specification • What sort of system is required? • stand alone computer(s) • how many, what sort? • local area network • what type, topology? • mobile computer(s): laptops, docking stations • space considerations: desktop, towers, LCD’s • printers: what sort, how many, what capabilities? • Cost and price performance index (PPI) • divide performance (measured somehow) by cost • Other factors may also be important • e.g. reliability, company reputation, service

System Types • Home PC’s • complete, integrated packages designed for novice • complete hardware, with bundled software • Multimedia PC’s • high specification, with large RAM, HD and monitor • high spec graphics and sound cards, DVD, speakers • Business PC’s • usually just the system box and monitor • often OS software only; printers, etc, are all optional extras • Network PC’s • designed to be network components • clients, servers; (Ethernet) NIC plus software

Main Hardware Components • Processor: the main governor of speed • the processor manufacturer and type • e.g. Intel Pentium, AMD • the processor speed • 1.2 GHz to 3.6 GHz, dual/quad core widely available • RAM: has significant effect on system speed • minimum 1Gb, typical 2Gb, high 4Gb+ • Hard disk: governs both capacity and speed • Typically 500Gb+ • Monitor+ graphics card: v. important, often neglected • determines screen type and size, maximum resolution

Networks • There are many decisions to be made in specifying a total network solution • usually some form of specialist knowledge is required if more than a simple network is needed • although everyone is connecting to the Internet • this has been made relatively easy using integrated software • A simple network may be a good solution for many small offices • several users can share office software, data and hardware services such as printers, faxes, modems • extra hardware, software and cabling may be required

Laptops – Pros and Cons • Laptop PCs are popular with users but can encourage poor security. • Laptops are frequently stolen. • Laptops are more expensive. • Laptops tend to be slower (there are no quad core laptops available) • Laptops are harder to upgrade. • Only buy your staff laptops if they really need to take work onto other sites (e.g. To demonstrate a new product)

Other Features - 1 • The quality of the case is an often neglected feature: • Check the size of the power supply. • Will it cope with extra devices? • Is it from a quality manufacturer? • A ‘silent fan’ can improve the quality of the office environment. • Cheap cases can make access to components difficult.

Other Features - 2 • When considering solutions for businesses, there are other features that may be included • backup devices • if the system, particularly user data, is critical to the business then backup device and strategy must be considered • tape, e.g. DAT; optical, e.g. CD-R, CD-RW, DVD-RW; magnetic e.g. external HD • UPS: uninterruptable power supply • uses batteries to keep the system running, or at least to allow it to shut down cleanly, in the event of a power cut • RAID: redundant array of independent disks • several physical disk drives hold exactly the same data • if one disk crashes the system is unaffected • sometimes allow ‘hot-swapping’ of crashed drives

Software • Remember: the point of the computer system is the software services available, not flashy HW! • it is hard to avoid Microsoft Office as the best choice • it’s standard (widely used) • but note that a full professional version costs c. £600! • alternatives: OpenOffice (free), WordPerfect, SmartSuite • for accounts, graphics, software development and other utilities the choice is a lot more difficult • Corel, Pegasus, Sage, Symantec, Netscape, Visual Studio • for professional database management • SQL Server – a heavyweight database application other options include Oracleor IBMsolutions. Microsoft Access suitable only for small applications. • dedicated software solutions for specific needs

Printers • The main points to establish are • how many pages are to be printed each day, month? • what sort of quality is required? • dpi, colour • what are the ongoing running costs (consumables)? • a low cost printer may cost more in long run • are there any special requirements? • It is very rare for printers to be fully loaded • therefore they are obvious candidates for sharing • it is not necessary to install a LAN to share printer access • printer sharers / buffers can allow multiple connections • printers may be served off PC’s or straight off network

Future Proofing • There is a common misconception that by spending a little more money at the outset the purchased system can be made ‘future-proof’ • hardware capabilities and software requirements are continuing to increase as fast as ever • there is no sign of any let-up in either • any system purchased now will seem archaic in 3 years • it is better to allow for the possibility of upgrading • Another misconception is that it may be worth delaying a while to wait for prices to come down • by this logic you will never purchase a computer

Upgrading

Upgrading • Upgrading possibilities and principles • most components (except in laptops) can be upgraded • some upgrades can be tackled by almost any user • extra RAM, extra hard disk, expansion cards • some are harder and may not be worthwhile • motherboard, processor • Drive bays, slots and ports • most desktop / tower cases have physical space (bays) • either • Normally 4 SATA connectors (for HD and DVD, Blu-Ray) • Probably one IDE connector (some IDE DVDs still available) • usually additional RAM slots (DIMMS, DDR) • usually card slots (3-5 PCI, maybe others, e.g. PCI Express) • serial / parallel ports can connect backup devices

Upgrading the Processor • It is usually possible on most motherboards to unplug the processor and plug in a quicker one • however, there are issues with socket design • not all processors plug into the same socket • there are also issues with (system) bus speeds • quite often only a small improvement in system speed • processors are delicate and have hundreds of pins! • Some motherboards / systems are providing the facility for installing more than one processor • the speed increase is dependent largely on the ability of the operating system to take advantage of the HW

Upgrading Memory • Increasing the RAM often has a dramatic effect on system performance • programs and data are loaded into RAM when needed • if multiple programs with large data are being run then both may be ‘swapped’ out to hard disk (the swap file) • information transferred to and from the hard disk by the OS • most new PC’s now have 3 DDR slots • Generally better to buy large memory chips than several small ones. • DDR can easily be added as required • Note the wide fluctuations in RAM prices • Large price increases and decreases due to fluctuations in world markets.

Upgrading Hard Disks • Adding a new (second or third) hard disk is an easy way to increase the lifetime of a system • a faster hard disk can speed up a system, particularly if swapping occurs often & the swap file is on the fast HD • USB devices are easy to install but are slower • if the new fast HD is installed as C: drive then all OS and application SW may need to be re-installed • there are utilities available to automate such drive copying

Expansion Cards • Expansion cards are available to add all sorts of facilities onto the ‘basic’ PC • SCSI cards: provide a SCSI bus connection • can be used for CD-ROMs (to free up IDE for disks) • can be used for SCSI disks: large capacity, but expensive • many scanners are SCSI • Basic systems are now often included on the M/B • sound / graphics / multimedia cards • network interface card(s): one per protocol • internal modem / terminal adaptor cards • may free up a serial port, may be faster • specialist cards: e.g. video conferencing

Maintenance and Care

Warranties • All computer systems will come with a warranty (guarantee that they will work) when purchased • often this will only last, for example, one year • this is not sufficient for a business where the system is critical and must last, for example, three years • sometimes extended warranties can be specified at time of purchase (very rarely afterwards) • these will typically be up to three years from purchase date • Often there are quite strict (and often silly) terms and conditions on warranties • e.g. the warranty is invalidated if the case is opened • how can the user install an add-on card?

Maintenance and Service • Most manufacturer warranties are ‘return to base’ • if equipment fails, the user must return (post/courier) it back to the manufacturer, who then repairs / replaces it • the user is without the equipment while it is fixed • This is probably inadequate for business use • service or ‘on-site maintenance’ contracts available • an engineer is dispatched within a certain ‘guaranteed’ time • e.g. four hour / eight hour / next day response • if equipment fails, the engineer will bring the replacement to the site so that the downtime is minimised • can be expensive (almost as much as purchase price)

Health and Safety • All electrical equipment must conform to European health and safety legislation when sold • this may not seem important for home use, but may be very important to businesses • an employer (or you) don’t want to be sued for allowing employees to operate dangerous equipment • however, again there may be problems if computers are upgraded by ‘non-professionals’ • safety checking may have to be performed after upgrade • always check this in a commercial environment • Chairs, desks and VDU viewing positions are all covered by health and safety legislation. • Disposal of equipment to follow the Waste Electrical and Electronic Equipment directive (Retailers to collect free apart from a small handling fee)

Care and Cleaning • If a computer is to stay in good working for three or more years it requires some looking after • Inside the case • Dust can be conductive and cause problems on the main board. • Optical mouse • Can get clogged with fluff. • the keyboard gets dirty • keycaps can usually be removed and dirt & grime removed • the screen gets dirty • can be cleaned with a specially coated cloth • Rough treatment can cause significant damage • moving (esp. shocking) a computer can permanently damage the hard disk (portables more robust)

And Finally! • There are computers other than Intel based PC’s • other personal computers • Apple • other network solutions • Sun • There are operating systems other than Microsoft • LINUX: UNIX for IBM / Intel PC’s • Apple OS: a variation on UNIX • UNIX / Solaris

Summary • System life cycle • determining requirements, sourcing • System specification • costs, PPI (price performance index) • types: desktop, laptop, server / workstation • the main components and factors • Upgrading • processor, memory, hard disks, expansion cards • Maintenance and care • warranties, maintenance, health and safety, care

CSCI1412 Lecture 13