CSCI1412 - System Specification

CSCI1412Lecture 13Hardware 7System SpecificationDr John Cowell

phones off (please)1OverviewSystem life cycledetermining requirements, sourcingSystem specificationcosts, PPI (price performance index)types: desktop, laptop, server / workstationthe main components and factorsUpgradingprocessor, memory, hard disks, expansion cardsMaintenance and carewarranties, maintenance, health and safety, care2System Life Cycle3System Life CycleAscertain the user requirementsDetermine hardware and software neededIdentify alternative suppliersPurchase equipmentInstall the hardware and softwareTrain the usersRun the systemoptional: upgrade the systemmaintain the system4Ascertain User RequirementsThis means ask the users what they want!find out what they want to actually accomplishnot asking the users what they think they want to buytypical information to extractwhat sort of documents, types of workletters, reports, memos, etc: word processingaccounts, numerical analysis: spreadsheetdata manipulation, storing, retrieving: databasehow many documents, volumes of workhow much sharing of informationnetworking: LAN, WAN accessbudgets, user knowledge, environments, expectationsDo they have any existing IT equipment?5Determine SolutionThis means tell the users what they need!use your skill and knowledge as the expert to specify the hardware and software requirements of the usersthe difficulty and skill is in recommending systems that are adequate for the job (for the lifetime), but without costing (wasting) money through over specificationthere 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 solutionotherwise migration will have to be planned / costed6Selection and PurchasingMany organisations require three or more quotesperhaps obtain quotes from three types of sellersmanufacturing company (e.g. IBM)direct sales (e.g. DELL)box-shifter (e.g. PC World)When purchasing be careful of:changing specifications and / or pricesterms and conditions: delivery charges, warrantyThere are options on method of purchaseoutright purchaseleasing (pay amount each month over e.g. three years)can be attractive for businesses (servicing often included)7Installation, Training & MaintenanceFor most commercial systems installation, training & maintenance should be included in specificationthis is expected and companies are prepared to pay for these servicesOnce installed, system must run for several yearsusually at least three years, often five or moreThe system should have enough capacity to copemay need to be upgraded during lifetimeNormally, some consideration will be needed of system reliability and long term maintenancemaintenance / service contracts included in purchase?8System Specification9PC SpecificationWhat sort of system is required?stand alone computer(s)how many, what sort?local area networkwhat type, topology?mobile computer(s): laptops, docking stationsspace considerations: desktop, towers, LCDsprinters: what sort, how many, what capabilities?Cost and price performance index (PPI)divide performance (measured somehow) by costOther factors may also be importante.g. reliability, company reputation, service10System TypesHome PCscomplete, integrated packages designed for novicecomplete hardware, with bundled softwareMultimedia PCshigh specification, with large RAM, HD and monitorhigh spec graphics and sound cards, DVD, speakersBusiness PCsusually just the system box and monitoroften OS software only; printers, etc, are all optional extrasNetwork PCsdesigned to be network componentsclients, servers; (Ethernet) NIC plus software11Main Hardware ComponentsProcessor: the main governor of speedthe processor manufacturer and typee.g. Intel Pentium, AMDthe processor speed1.2 GHz to 3.6 GHz, dual/quad core widely availableRAM: has significant effect on system speedminimum 1Gb, typical 2Gb, high 4Gb+Hard disk: governs both capacity and speedTypically 500Gb+Monitor + graphics card: v. important, often neglecteddetermines screen type and size, maximum resolution 12NetworksThere are many decisions to be made in specifying a total network solutionusually some form of specialist knowledge is required if more than a simple network is neededalthough everyone is connecting to the Internetthis has been made relatively easy using integrated softwareA simple network may be a good solution for many small officesseveral users can share office software, data and hardware services such as printers, faxes, modemsextra hardware, software and cabling may be required13Laptops Pros and ConsLaptop 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)

14Other Features - 1The 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.

15Other Features - 2When considering solutions for businesses, there are other features that may be includedbackup devicesif the system, particularly user data, is critical to the business then backup device and strategy must be consideredtape, e.g. DAT; optical, e.g. CD-R, CD-RW, DVD-RW; magnetic e.g. external HDUPS: uninterruptable power supplyuses batteries to keep the system running, or at least to allow it to shut down cleanly, in the event of a power cutRAID: redundant array of independent disksseveral physical disk drives hold exactly the same dataif one disk crashes the system is unaffectedsometimes allow hot-swapping of crashed drives16SoftwareRemember: the point of the computer system is the software services available, not flashy HW!it is hard to avoid Microsoft Office as the best choiceits standard (widely used)but note that a full professional version costs c. 600!alternatives: OpenOffice (free), WordPerfect, SmartSuitefor accounts, graphics, software development and other utilities the choice is a lot more difficultCorel, Pegasus, Sage, Symantec, Netscape, Visual Studiofor professional database managementSQL Server a heavyweight database application other options include Oracle or IBM solutions. Microsoft Access suitable only for small applications.dedicated software solutions for specific needs17PrintersThe main points to establish arehow many pages are to be printed each day, month?what sort of quality is required?dpi, colourwhat are the ongoing running costs (consumables)?a low cost printer may cost more in long runare there any special requirements?It is very rare for printers to be fully loadedtherefore they are obvious candidates for sharingit is not necessary to install a LAN to share printer accessprinter sharers / buffers can allow multiple connectionsprinters may be served off PCs or straight off network18Future ProofingThere is a common misconception that by spending a little more money at the outset the purchased system can be made future-proofhardware capabilities and software requirements are continuing to increase as fast as everthere is no sign of any let-up in eitherany system purchased now will seem archaic in 3 yearsit is better to allow for the possibility of upgradingAnother misconception is that it may be worth delaying a while to wait for prices to come downby this logic you will never purchase a computer19Upgrading20UpgradingUpgrading possibilities and principlesmost components (except in laptops) can be upgradedsome upgrades can be tackled by almost any userextra RAM, extra hard disk, expansion cardssome are harder and may not be worthwhilemotherboard, processorDrive bays, slots and portsmost 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 devices21Upgrading the ProcessorIt is usually possible on most motherboards to unplug the processor and plug in a quicker onehowever, there are issues with socket designnot all processors plug into the same socketthere are also issues with (system) bus speedsquite often only a small improvement in system speedprocessors are delicate and have hundreds of pins!Some motherboards / systems are providing the facility for installing more than one processorthe speed increase is dependent largely on the ability of the operating system to take advantage of the HW22Upgrading MemoryIncreasing the RAM often has a dramatic effect on system performanceprograms and data are loaded into RAM when neededif 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 OSmost new PCs now have 3 DDR slotsGenerally better to buy large memory chips than several small ones.DDR can easily be added as requiredNote the wide fluctuations in RAM pricesLarge price increases and decreases due to fluctuations in world markets.23Upgrading Hard DisksAdding a new (second or third) hard disk is an easy way to increase the lifetime of a systema faster hard disk can speed up a system, particularly if swapping occurs often & the swap file is on the fast HDUSB devices are easy to install but are slowerif the new fast HD is installed as C: drive then all OS and application SW may need to be re-installedthere are utilities available to automate such drive copying24Expansion CardsExpansion cards are available to add all sorts of facilities onto the basic PCSCSI cards: provide a SCSI bus connectioncan be used for CD-ROMs (to free up IDE for disks)can be used for SCSI disks: large capacity, but expensivemany scanners are SCSIBasic systems are now often included on the M/Bsound / graphics / multimedia cardsnetwork interface card(s): one per protocolinternal modem / terminal adaptor cardsmay free up a serial port, may be fasterspecialist cards: e.g. video conferencing25Maintenance and Care26Warranties All computer systems will come with a warranty (guarantee that they will work) when purchasedoften this will only last, for example, one yearthis is not sufficient for a business where the system is critical and must last, for example, three yearssometimes extended warranties can be specified at time of purchase (very rarely afterwards)these will typically be up to three years from purchase dateOften there are quite strict (and often silly) terms and conditions on warrantiese.g. the warranty is invalidated if the case is openedhow can the user install an add-on card?27Maintenance and ServiceMost manufacturer warranties are return to baseif equipment fails, the user must return (post/courier) it back to the manufacturer, who then repairs / replaces itthe user is without the equipment while it is fixedThis is probably inadequate for business useservice or on-site maintenance contracts availablean engineer is dispatched within a certain guaranteed timee.g. four hour / eight hour / next day responseif equipment fails, the engineer will bring the replacement to the site so that the downtime is minimisedcan be expensive (almost as much as purchase price)28Health and SafetyAll electrical equipment must conform to European health and safety legislation when soldthis may not seem important for home use, but may be very important to businessesan employer (or you) dont want to be sued for allowing employees to operate dangerous equipmenthowever, again there may be problems if computers are upgraded by non-professionalssafety checking may have to be performed after upgradealways check this in a commercial environmentChairs, 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)29Care and CleaningIf a computer is to stay in good working for three or more years it requires some looking afterInside the caseDust can be conductive and cause problems on the main board.Optical mouseCan get clogged with fluff.the keyboard gets dirtykeycaps can usually be removed and dirt & grime removedthe screen gets dirtycan be cleaned with a specially coated clothRough treatment can cause significant damagemoving (esp. shocking) a computer can permanently damage the hard disk (portables more robust)30And Finally!There are computers other than Intel based PCsother personal computersAppleother network solutionsSunThere are operating systems other than MicrosoftLINUX: UNIX for IBM / Intel PCsApple OS: a variation on UNIXUNIX / Solaris31SummarySystem life cycledetermining requirements, sourcingSystem specificationcosts, PPI (price performance index)types: desktop, laptop, server / workstationthe main components and factorsUpgradingprocessor, memory, hard disks, expansion cardsMaintenance and carewarranties, maintenance, health and safety, care32