COMPUTER HARDWARE REPAIRS AND MAINTENANCE · COMPUTER HARDWARE REPAIRS AND MAINTENANCE Presentaon By Akusa Peter Aker Assistant Chief Programme Analyst Na#onal Judicial Instute, Abuja

COMPUTERHARDWAREREPAIRSANDMAINTENANCE

Presenta(onBy

AkusaPeterAkerAssistantChiefProgrammeAnalystNa#onalJudicialIns#tute,Abuja.

AttheWorkshopforInforma>onandCommunica>onTechnologyStaff,organisedbytheNa>onalJudicialIns>tute,

22nd-24thMay,2017

1ComputerHardwareRepairsandMaintenance

Objec>ves KnowledgeofComputerHardware Iden(fycomputerhardwareIssues/Problems determinefaultyComputerhardware KnowBasiccomputertroubleshoo(ng(ps Knowledge of Opera(ng System and deviceDrivers Iden(fyhardwarePeripherals Basicknowledgeofsafeguardinghardware Apply the knowledge torepair/maintainacomputer.


LearningtheCOMPUTERBasics


WhatisaComputer?

•  An electronic device, opera(ng underthe control of instruc(ons stored in itsownmemory,thatcan:– Acceptdata(input)– Processthedataaccordingtospecifiedrules(process)

– Produceresults(output)– Store the results (storage) for futureuse.

4ComputerHardwareRepairsand

Maintenance

WhatisaComputer?...


Examples and type of computer


SmartphoneNotebook

Desktop

PDA

Tablet

Mainframe

Supercomputers

WearableComputers

Computer System is functional only if :

users

SoTware

Hardware


Basic Hardware components

Hardware represents the physical and tangible components of a computer i.e. the components that can be seen and touched. Examples of Hardware are following:Inputdevices:keyboard,mouseetc.Outputdivices:printer,monitor,speakeretc.Secondarystoragedevices:Harddisk,CD,DVDetc.Internalcomponents:CPU,motherboard,RAMetc.


ComputerHardware


HardwareComponents

Case/SystemUnit. Thecomputercase(also called a tower ) is the box thatenclosesmanyoftheparts/componentsofthecomputer

Power Supply or SMPS(SwitchedModePower Supply). Converts AC voltagefrom the wall outlet to DC voltage thecomputer can use. It supplies DCvo l tages for in terna l computercomponents and has a fan to keep thecomputercool.

Processor & Fan. Theprocessor isthemain “brain” of a computer systemwhi le the Fan help to preventoverhea(ng of the various electroniccomponents

Motherboard. Themotherboardisalarge electronic board that is used toconnect the power supply to variousotherelectronicparts,andtoholdthesepartsinplaceonthecomputer.

RAM(RandomAccessMemoryq shorttermmemorythat isusedtostoredocumentswhiletheyarebeingprocessed.q The amount of RAM in a computerdeterminethespeedofacomputer.q RAM a]aches to the motherboard viasomespecificslots.

NIC (Network Interface Card) used todescribetoolsthatallowyourcomputerto connect and communicate withvariousinputandoutputdevices.


Hardware Components cont…

Drives.q A computer’s drives are the devicesused for long term storage ofinforma(on. e.g. Hard Disk, Flash Disketc.q harddrive-Orharddisk,isacommonstorage device for maintaining filesinside the computer, usually mountedbeloworbesidethefloppydrive.q CDdrive–q Holds disks (CDs) that have data,music,orsocwareapplica(ons.q DVD (Digital Versa>le Disk) drive -Popular alterna(ve to a CD drive thatsupportsCDsaswellasmusicandvideoDVDs.q FlashDrive-

NIC(NetworkInterfaceCard)(N IC ) i s a computer hardwarecomponent that allows a computer toconnecttoanetwork.NICsmaybeusedforbothwiredandwirelessconnec(ons.A NIC is also known as a networkinterface controller (NIC) or networkcard, LAN card, network adapter ornetworkadaptercard(NAC).

Computer Hard disk are of two types, IDE(Integrated driveelectronics)-q Has a ribbon like cable with either a 40-pin or 80-pinconnector.q TheIDEdatatransferinterfacerunsinparallel.SATA(SerialAdvancedTechnologyA\achment)-q has a narrower cable with a split data and powerconnec(ons.q Ithasa7-pincableandamuchfasterdatatransferrate.q MostmotherboardsnowsupportSATAq Well know hard disk manufactures are Seagate, WesternDigitaletc.

Peripheralhardware.q Are the computer components thatarenotfoundwithinthecomputercaseq It is defined as any auxiliary devicethat connects to and works with thecomputer in some way. E.g. mouse,microphone and keyboard, monitor,printerandspeakersetc. 11ComputerHardwareRepairsand

Maintenance

WhatisComputerPorts?

Port: Is a connector on the motherboard or on aseparateadapterthatallowsadevicetoconnectto a computer; these may include keyboard,mouse, serial,parallel,network, sound,or videoports.

q Ports vary with the type of equipment thatconnectstotheports.

q Ports have gradually changed over (me ascomputers have changed to become faster andeasiertoworkwith.


Maintenance

Portcontd…

q Male ports – Have pins thatprotrude out from the connector andrequireacablewithafemaleconnector.

q Femaleports. Have holes in the connector to accept themalecable’spins.


Ports…

•  D-shell connector–Aconnectorwithmorepinsor holes on the top row thanon the bo]om sothat a connected cable can only be a]ached inonedirec(onandnotaccidentallyconnectedthewrong way; generally represented with thele]ersDBandthenumberofpinssuchas,DB-9,DB-15,orDB-25.

•  DIN connector – Round with small holes andnormally keyed; the keyboard and mouse areusually this typeof connectorwitheither5or6pins.


USB.q A4-wireconnectortypeofportq  Different models (USB 1.0, USB 2.0andUSB3.0),q  Connect all kinds of external USBdevices e.g. external hard disk, printer,scanner,mouse,keyboardetc.q Most of the computers provide twoUSBorthreeUSBportsasminimum.q Data travels at 12 megabits persecondsq USBcompliantdevicescangetpowerfromaUSBport

TRS.TRS((p,ringandsleeve)portsAlsoknownasportsformini-jacksoraudiojacks.Theyarecommonlyusedtoconnectaudiodevicessuchasheadphonesandmicrophonestocomputers.

HDMI(HighDefini(onMul(mediaInterface)q provides an interface between anyaudio/video source, e.g.DVDplayer, orA/Vreceiverandanaudioand/orvideomonitor, such as a digital television(DTV),q HDMI supports standard, enhanced,or high-defini(on video, plus mul(-channeldigitalaudioonasinglecable.

SerialPort.D-ShellConnectorq usespinconnectors,q AlsoknownasaCOMport)canbea9-pinFemaleD-shellconnectorq Datatravelsat115kilobitspersecond

ParallelPort.(D-ShellConnector)q Thislongandslenderportisalsonolongercommonlyused,q Themostcommonparallelporthasholesfor25pins,q Usedforscannersandprintersq Alsocalledprinterport

PS/2.DINConnectorsq Mostdesktopcomputershavetwooftheseroundportsforsixpinconnectors,oneforthemouseandoneforthekeyboard.

GAMEPORT.D-ShellConnector.A15portpinusedtoconnectgames


IEEE1394ports–q A serial technology developed byApple Computer some(mes called theFireWireport.q A6-wirecable/port(4fordata,2forpower)q  speeds of 100, 200, 400, 800, and1200Mbps.

EthernetPortq ConnectstoanetworkandhighspeedInternet.q Connectnetworkcabletoacomputer.q ThisportresidesonanEthernetCard.q Data travels at 10 megabits to 1000megabits per seconds depending uponthenetworkbandwidth.

VGAq Athreerow,q 15-pin female D-shell connector fornewerVGA,SVGA,XGA,SXGA,orUXGAmonitorsq Connects monitor to a computer'svideocard.q Similar to serial port connector butserial port connector has pins, it hasholes.

ModemPortq ConnectsaPC'smodemtothetelephonenetwork. GamePort.

q Connectajoys(cktoaPCq NowreplacedbyUSB

SerialPort.MaleD-ShellConnectorq usespinconnectors,q itisnolongercommonlyused,q  It was used for printers, mice,modems and a variety of other digitaldevices.q Datatravelsat115kilobitspersecond


ArrangementofcomputerComponents/Ports


ComputerSoTware


WhatisaSoTware?SoTware. Is a set of programs, which is designed to perform a well-defined func(on. A Program is a sequence of instruc(onswri]entosolveapar(cularproblem.

TypesofsoTwareq SystemSoTwareØ  The system socware is collec(on of programs designed to

operate, control, and extend the processing capabili(es ofthecomputeritself.

Ø  System socware are generally prepared by computermanufactures.

Ø  System socware serves as the interface between hardwareand the end users. e.g. Opera(ng System, Compilers,Interpreter,Assemblersetc.


Software Types and Categories… Applica>onSoTware:

q Applica(on socware products are designed to sa(sfy apar(cularneedofapar(cularenvironment.

q Applica(onsocwaremayconsistofasingleprogram,suchasaMicrosoc'snotepadforwri(ngandedi(ngsimpletext.

q  It may also consist of a collec(on of programs, ocen called asocware package, which work together to accomplish a task,such as a spreadsheet package. e.g. Payroll Socware, StudentRecord Socware , Inventory Management Socware, MicrosocOfficeSuiteSocware,AdobePremieresuitesetc.

•  U>litySoTware. Allowacomputer toperformtasks thatarenot part of the opera(ng system, but are s(ll prac(cal anduseful. For example, a u(lity socware might instruct acomputeronhowtocopy(burn)informa(ontoaCD-ROMdisk,oritmightbeanan(-virusprogram


Proprietary Software vs. Open Source Software

Ø They are proprietary, which meansthat their use and modifica(on arerestricted.Ø Theycanbequitecostlytobuylicensesfor.Ø  they are not adaptable tomeet localneeds.Ø  Someusers,par(cularly indevelopingcountries, illegally use unlicensed (alsoknownaspirate)copiesofthissocware.Ø  This is legally unwise, and can alsokeep the user from accessing importantsocwareupdates.

Ø Users who cannot afford proprietarysocware or prefer socware that can belocally modified, can choose to use opensource (ocencalled freeandopensourceorFOSS)socware.Ø  For most of the standard computeruses, an open source socware op(on isavailable. E.g. Linux family of opera(ngsystems (which includes Ubuntu, and theOpenOffice.orgproduc(vityprograms.Ø  T h e S o u r c e F o r g e w e b s i t e(www.sourceforge.net) isagoodresourcefor finding and downloading open sourceprograms.


ExamplesandtypesofsoTware

SystemSoTware:e.g.Opera>ngsystems SystemsoTware:e.g.U>li>essoTware

Applica>onsoTware:e.g.MicrosoTOfficesuites 22ComputerHardwareRepairsandMaintenance

Rela>onshipBetweenHardware/SoTware


Rela>onshipbetweenHardwareandSoTware

  Hardware and software are mutually dependent on each other. Both of them must work together to make a computer produce a useful output.

  Software cannot be utilized without supporting hardware.

  Hardware without set of programs to operate upon

cannot be utilized and is useless.   To get a particular job done on the computer, relevant

software should be loaded into the hardware . i.e. a device driver is needed.

  Hardware is a one-time expense.


Adevicedriverisaprogramthatcontrolsapar(culartypeofdevicethatisa]ached to your computer. There aredevicedrivers for printers, displays,CD-ROM readers, diske]e drives etc.When you buy an opera(ng system,manydevicedriversarebuiltintotheproduct.

 Software development is very expensive and is a continuing expense.

  Different software applications can be loaded on a hardware to run different jobs.

 A software acts as an interface between the user and the hardware.

  If Hardware is the 'heart' of a computer system, then Software is its 'soul'. Both are complimentary to each other.

ComputerHardwareRepairsandMaintenance 25

Rela>onshipbetweenHardwareandSoTware

Iden>fyingComputerProblems/Issues


HardwareorSocwareProblem?


TipsforDis>nguishingBetweenHardwareProblemsandSoTwareProblems…

q Were there any loud noises or smoke whenthe problem first appeared? Then it isprobablyahardwareproblem,withthemostlikely culprit being theSMPS(SwitchedModePowerSupply)unit.

Note: Make sure you reduce possible“external” problems before proceeding.This means unplug any external devices(such as hard drives, scanners or printers),andremoveanyUSBFlashdisk, CDorDVDdisksfromtheirdrives.


TipsforDis>nguishingBetweenHardwareProblemsandSoTwareProblems…q Is thecomputeren(relydead?Or thescreenblank?Or

the screen showing a poor/incomplete picture? Thesefaultsareprobablyalsoduetohardwareproblems.

q Doesthecomputerproduceaseriesofbeeps? Thisisa

code that can be used to dis(nguish some hardwareproblems.

q Does the system give any error codes or descrip(ons

while boo(ng? These can be due to hardware orsoTwareproblems. Takecarefulnoteofallinforma(ongivenintheerrorcode.



q Does the computer p roduce er rorinforma>onacer ithasbootedoronlywhenyou open specific programs? These errorcodesareprobablyduetosoTwareproblems.

q Have any recent changes been made tohardware or soTware (including BIOSsepngs)?Ifso,thesearelikelyculprits.



q Hasthecomputerbeenexposedtovirusesorothermalware? This could be a cause of soTwareproblems.

q UsetheDeviceManager.TheDeviceManagerwilllistall of thehardware devicesinstalled on a PC. Anydevice with a problem willhaveawarningsymbolnextto it,anddoubleclickingonthat device would givedeta i l s and suggestedremediesfortheproblem.

Warningsymbol31ComputerHardwareRepairsand

Maintenance

ComputerMaintenance


NOTE:Preven>on(maintenance)isbe]erthancure(Repairs).

Computermaintenanceisnecessary…

v Check harmful materials e.g. dust , virus,outdated soTware, faulty electrical Power/gadgete.g.cables,sockets,extensionsetc.

v Checkanymalfunc(onsofperipherals.v Propermaintenancehelpstokeepthecomputerrunningsmoothlyforyears.


ComputerMaintenance…

Thesesteparefortheexperienceandprofessionalsonly!!

Cau>on!!!•


Computermaintenance

Improvingslowperformance

DustControl.Ø Dustisveryharmfulforcomputerparts.Ø Excess dust can cause mechanical failures,par(cularly on computer components withmovingparts.

Ø Computers should be dusted regularly byusingcompressedairmachines.


Maintenance

Computermaintenance:Improvingslowperformance

DiskDefragmenter.Used to organize files on the harddrive and op(mize free space,i m p r o v i n g t h e s p e e d a n dperformanceofthecomputer.Someapplica(ons may fail outright if thediskbecomestoofragmented.

ScanDisk/CheckNow:Forharddisk faults,use scandisk/Checknowtoscantheharddiskforfaults and even repair them ifpossible. Thisop(onwillchecktheHarddiskforerrors.


Computermaintenance:improvingslowperformance

ExcessandUnusedFiles.

DiskCleanup:TheDiskCleanupU(litycandeterminewhichfilesonyourharddrivemaynolongerbeneededanddeletethosefiles.Inaddi(ontofreeinguppoten(allysignificantamountsofhard drive space.Using this u(lity regularly can improvesystemperformance.

q As a hard disk becomes full, the computer’sperformanceisreduced.q  It takesmore (me to find and access neededfiles.

q Defragmenta(on is not as successful due to alack of free space to temporarily move files towhiletheyarebeingrearranged.q Therefore, it iswise foracomputerusernot tokeepfilesthatarenolongerneeded.q Files that have been stored in a user’sdocumentsfolderthatarenolongerneeded(suchas extra photos or older versions of documents)shouldbedeleted.


AtypicalexampleofafullyloadedLocalHardDiskdrive



Dele>ngBrowsingHistory.§  Thebrowserstorestherecenthistoryofthewebpagesthattheuserhasviewed,

§  This make it easier tofindand load thesewebpagesagain.

§  The browser also stores other small bits ofinforma(onsuchasdataenteredintoformsandusernames or passwords if a user has asked aweb page to “remember me” (although this isnotagoodideaforsharedcomputers).

§  Thisstoredinforma(oncanbeeasilydeleted.39ComputerHardwareRepairsand

Maintenance


Startupfolder Someprogramswill automa(callyput a shortcut inthe Startup folder, forcing the program toautoma(cally launch when you turn the computeronorlogin.Some(mesthis isdesirable,some(mesnot. Either way, this prac(ce may slow yourcomputer down to various degrees, and with theprogram running all the (me, may slow down theperformanceofyourcomputer.

q DeletesomeoftheprogramsintheStartupfolder



SoTwareInventoryOncetheharddiskbecomesfull,acomputer’sperformance is reduced. To avoid installingsocware that are not necessary, systeminventory will require you knowing whatsocware is needed/wanted on yourcomputer.

Note: Please use cau(on when uninstallingsocware. In order to reinstall, you will needtheoriginalsocwareinstalla(onfiles. 41ComputerHardwareRepairsand

Maintenance


ProtectyourPCfromcyber-threatsorMalwareThecyber-worldisfullofthreatssuchasviruses,spyware,Trojans,Wormsandetc.Thesecyber-threatscancausehugedilemmastoyourcomputer.These undesirable programs, which are usually added without a user’sknowledge,cansignificantlyslowdowntheperformanceofacomputer.

Thebestwaystopreventvirusinfec#onsare:

q  Keepingan(virussocwareuptodateandrunningscansonaregularbasis

q  Strict policies should be put in place to prevent virus infec(on e.g.

prohibi(ngtheuseofflashdrives,orrequireFlashdisktobescannedbeforeuse.

q  Other policy to consider is the prohibi(on of downloading, since

unsuspec(nguserscanaccidentallydownloadmalware.q  Afirewallmayalsobeusedtoblocksdangerousdownloads. 42ComputerHardwareRepairsand

Maintenance


UPDATINGSOFTWAREq  Itisimportantforacomputerusertofindand install socwareupdates inorder tohavewellperformingcomputers.

q  Upda(ngsocwarecanbedone inavarietyof ways, Automa>c Updates, Automa>cAlertsforUpdates,ManualUpda>ng,OfflineUpda>ng.



Overhea>ngExcessiveheatcancauseasignificantdecreaseincomputerperformance.

q In order to cool down an overheated computerprocessor, avoidopera(ngthecomputer ifthecaseisinanenclosedspace.(suchasadrawerorcupboard).

q Alsocooltheroomwithfansorair-condi(oning.q Also verify that all of the fans in the computercasearefunc(oningproperly.Note:Modern computers have safeguards thatshut down the system if a component isoverhea(ng.



InsufficientRAM Computer need sufficient RAM to performthedesiredfunc(onsoncethememoryisnotsufficient.Theperformancewillbeslow.Thisproblemismost likely if thecomputer israther old and has had a newer (and morememory demanding) opera(ng systeminstalled.



Endurance: Lastly, one important hint to also keep inmindwhenyouareusingacomputeristobepa(ent. Some(mes the computer has to“think”too!(process)Note:Avoidopeningtoomanyprogramsata(me.Itwillreducetheperformanceofthecomputer.


HARDWAREREPAIRS


HardwareRepair

q  Repairmeans to rec(fy, to fix the problem either in the hardware orsocware.itmayalsoincludereplacementofacomponentthatisfaulty.

q  Itisanessen(alpartoftroubleshoo(ng.q  In finding or analyzing the faults, it can be decidedwhich hardware or

socwarecanberepaired.


GENERALGUIDELINESFORREPAIRINGCOMPUTERS

Forrepairingortrouble-shoo(ngacomputerusethefollowingguidelines:q  Gathertogetheryourtoolkit:e.g.airblowingmachine,screwdrivers,

socware,backupdisketc.q  CheckforpowerFIRST,beforedoinganythingelse.

10 - 15 percent of all computer Issues/Problems emanate from powersurge. Check this BEFORE doing anything else. Check to be sure if thecomputerispluggedintoanACoutletproperly.

q  Checkyourexternalconnec>onstothecomputer. Specifically,checkthemouse,keyboard,monitor,modemand/orprintercables,makingsurethatallaresecureandintherightsockets.

q  PerformthePowerOnSelfTest(POST)POSTisasetofproceduresthatacomputerrunsthrougheach(meit isturnedon.Itensuresthatallofthesystem'shardwareisworkingproperlybeforetryingtoloadtheopera(ngsystem.IfthecomputerdoesnotpassPOST,itwillnotboot.Tip:Makesurethecomputerturnson. Ifnothinghappens (no lights,nosound,nofans,etc.),thecomputerhasapowerrelatedissue.



q Ifthecomputeriss>llmalfunc>oning,goaheadthenandopenthecase. Check to see that all of the cards are fully pressed downintothebusconnec(ons,thatanysocketedchipsarefullypressed into their sockets, and that all cable connec(onsare fully a]ached. Make sure that the drive cables area]achedcorrectly.

q Cleananydustorforeignmaterialoutofthecasewhileitisopen.Dustcancauseoverhea(ngproblemsandelectricalshorts.Some(mes, insectswillnest inside thecaseaswell.Allofthisneedstobecleanedoutbeforeyoucloseupthecase.Take precau(ons to avoid inhaling excess dust, andconsiderusingprotec(veeyewareifnecessary.



q  Try to boot the computer to the hard drive, or to a bootable CD/DVDdiskifnecessary.Some(mestheharddiskwillbecomecorruptedbyauser,orbyavirus.

q  Check the CMOS setup program, and correct any configura>onproblems. Iftheinforma(oninCMOSRAMaboutyourPC'sconfigura(onhasbeenchanged,oriftheba]eryhasdied,yourcomputerwillnotbootcorrectly,oritwillnotrecognizecertaincomponents.

q  Lookforunwantedchanges.

Someonemayhaveturnedthebrightnessdownonamonitor,ortheLANstaffmayhavechangedyourPC'sconfigura(onwithoutyourknowledge(or approval), or an installa(on program may have corrupted yoursocware. Look for recent changes in your system's opera(on. Youmayneedtorunanuninstallerprogramtoremedysocware-relatedproblems.

q  Isolatetheproblemtoonepieceofhardware,oronesoTwarepackage.q  Whenallthesefails,thenconsultaprofessional.


Computerissues/Problemsandthe(pstotroubleshootandfix/repairs.Thecomputerisunabletostartup–Ifthecomputerdoesnotturnonwhen

you press the power bu]on, the following sugges(onsmay help you todeterminewhythecomputerwillnotstartup.

q  Firstofall,checkifthecomputerispluggedintoanACoutletproperly.q  Pluganotherelectricaldeviceintotheoutlettobesurethattheoutletis

providing adequate power. A surge protector can be used in this case,because voltage surges can be very damaging to computers and otherelectricalcomponents.ThenputonthesystemtoperformaPOST.

q  AcerthePOSTanditisconfirmsthat,thecomputerisproducingallofthe

usual startup sounds and lights, but the monitor is not displaying anyinforma(on,perhapsthereisaproblemwiththemonitor.Makesurethatit is connected to a power source, and also that the VGA cable isconnectedtothecomputer.


Maintenance

Computerissues/Problemsandthe(pstotroubleshootandfix/repairs...

Thecomputerscreenisblank If thescreen isblank, thecomputermaynotbesettodisplaytheimageonthecomputerscreen.

q First, check if the monitor is plugged in to apower outlet and is connected to the computersecurely and make sure the monitor powerbu]onison.

q If the power light is not on, it means that theoutlet is not delivering power to the monitor.Fixingthepoweroutletinsuchcasesshouldhelpsolvetheissue.


Computerissues/Problemsandthe(pstotroubleshootandfix/repairs...TheBluescreen-TheseerrorsareocencausedbyØ  Poorlyfunc(oningdevicedrivers,Ø  Hardware problems (such as memory, power supplies or system

overhea(ng),Ø  Problemswiththesystemsocware.Ø  Theop(onofSystemrecoveryandbackupservicewillrestoreyour

PCtoanearlierpointofstage.Youcanperformthisac(onwhilstyougetaBluescreenerrororsuddensystemcrashes.

NOTE:Backupserviceisanassurancethatyourdataissafe.Troublewithvideocard– Ifthepowerlightofthecomputerandmonitorisonandnothingcomesuponthescreenwhenyoustartyourcomputerthentheremustbesomethingwrongwithvideocard.Changeitsvideoorthegraphicscardwithanewone.



•  OS or some Socware is func(oning abnormally – If theOpera(ng System (OS) or some other socware isunresponsiveorrespondsabnormally, Immediate Solu>on:Restart your computer and runa virusscan.Note:Youshouldhavea reliablean(virussocware installedonthecomputertofixthisissue.

•  Windows do not boot properly – If windows do not boot

properlythenyoushouldreinstallwindowswiththewindowsrecoverydisk.Mostofthe(mes,thisshouldhelpyougetridoftheproblem.



The computer is on but not responding – the computer is on but notrespondingtosocwareorkeyboardcommands,thenitmustbefrozenorhalted.Immediatesolu>on:

Ø  Pressandholdthepowerbu]onforatleast5seconds,Ø  itwillbeturnoff.Ø  Nowrestartyourcomputer.Thisshouldfixtheproblem.

Anexternaldeviceisnotworking–Ifanexternaldevicedoesnotfunc(onasexpected.

Immediatesolu>on:Ø  turnitonaccordingtoManufacturersinstruc(on;Ø  be sure that all device connec(ons are secure and receiving electrical

powerØ  Besurethedeviceiscompa(blewiththeopera(ngsystem.Ø  Andthatthecorrectdriversareinstalledandupdated.


Yes

TroubleshootVideoorPowerSupplyProblem

Troubleshootbootdevice,Opera>ngSystemorApplica>onloadedintheStartupfolder.

TroubleshootPOSTerror

NO

NO

NO

Problem/Issues

PowerontheComputer

DoesaCursorappear?

DoesPOSTpass

successfully

DoesaComputer

bootsuccessfully

?

End

Yes

Yes

Trou

blesho

o>ng

Flow

chart


MostcommonBasiccomputerHardwareRepairs Replacing a Power Supply. The power supply

failureisacommonprobleminourcountry.Thisisduetoanunevenor“poor”voltageandpowersurges.

•  Replacing a Hard Drive or formaing andinstallingFreshOPERATINGSYSTEM.

•  ReplacingRAM. RAMcanfailorcanloosefromits housing and need to be reseated. If acomputer needs new or addi(onal RAM, it isimportant to make sure that the RAM used iscompa(blewith the computer system. RAM isvery easily damagedbyelectrosta(c charges, soit is very important for theuser tobegroundedbeforepickingupRAM.AlsoRAMshouldonlybehandledbytheedges.


Peripheral Hardware Use and Maintenance

Peripheral hardware will also last longer if it is well maintained.Peripheral hardware such as printers, scannerswill last longer if propercareaboutheat,dustandpowersurgecontrolistakingtoconsidera(on.

Troubleshoo>ngandfixingPrinterproblemsq  Let’sassumethatyourprinter’sdriversareup-to-date,q  andthatithasenoughpaperandinkortonertoprint.q  Tryturningtheprinteroffandon.q  Unplugtheprinterandplugitbackin.q  Check your printer’s print queue by looking for the printer icon in the

systemtrayanddouble-clickingit.q  Theprintqueueshowsyouthestatusofeach jobaswellas thegeneral

statusofyourprinter.q  makesurethat‘UsePrinterOffline’isn’tselected.q  Ensurethat‘UsePrinterOffline’isn’tchecked.q  Some(mes,prin(ngwhileyourprinteristurnedoffcancauseWindowsto

setyourprintertoworkoffline,andthatcanstalljobssentlater.


MALWARE


Virus

MalicioussoTware,isanysocwareusedtodisruptcomputeror mobile opera(ons, gather sensi(ve informa(on, gainaccess to private computer systems, or display unwantedadver(sing.ThesemalicioussoTwarefinditswayinto:

•  Bootsector•  FileAlloca(onTable•  Par((ontable•  .Comand.Exe.Files.


Deadlyeffectofvirus

q Deletefiles

q Changefiles,

q Stealimportantinforma(on,

q  loadunwantedapplica(ons

q Senddocumentsviaelectronicmail(e-mail),

q Crippleamachine’sOpera(ngsystem(OS),thebasicsocware

thatrunsthecomputer.


Viruswarningsigns

q  The computer’s performance slows down considerably.

q  Programs don’t function as thy should. They either don’t start, or if they start, they stop

or do not give the desired output.

q  Computer fails to boot.

q  Files and folders keep disappearing without anybody deleting them.

q  The computer crashes or freezes indiscriminately such as program not responding

errors.

q  The computer keeps showing out –of -memory space messages or strange dialog boxes.

q  Programs and windows popping up randomly.

q  Disk can not be accessed

q  New icons and programs get installed automatically.

q  Printing doesn't work correctly

q  Windows shuts down or restarts unexpectedly.

q  A partition in the system disappears automatically.

q  File size changes for no apparent reason

q  An increase in the number of files on the system when nothing has been added. 63ComputerHardwareRepairsand

Maintenance

AGoodVirusProtec>onProgramshould:Scanforviruses:

Shouldbeabletocheckyourdrivesforviruses,aswellastheRAMofyourcomputer,anddetectthepresenceofavirus.

Cleanupthevirus: must be able to get rid of the virus it finds on yourcomputer;otherwise,itisuseless.

ProtectyourSystemfromviruses:Musthavetheabilitytoloadapieceoftheprogramintomemoryatboot-up(me, toprotect you fromgepngavirusinthefirstplace.

ProvideAutoma>cupdates, Must regularlyandautoma(callycheckbackwiththemanufacturerforinforma(ononnewviruses,


Maintenance

CONCLUSION:BestPrac>cesandDosandDon’ts

q  Always ensure that the power has been turned off before installing ortroubleshoo(nganyhardwarepartofthecomputer.

q  Before opening a computer case, always unplug the power cord from your

computer.

q  Acerunpluggingthepowercordfromyourcase,Holdthepowerbu\oninforat

least5seconds.Thiswilldrainanyresidualelectricityfromthepowersupply

q  Alwaysgroundyourselftothecaseframewhiletouchinganyinsidecomponents.

This can be done by touching the case frame with your bare hand, or using a

clamp-ongroundingdevicemadespecificallyforthispurposeq  Keepallliquidsaway.q  Avoidinstallingcomponentswhenthecomputerisinopera(on.

q  Wheninstallingany,peripheralordevice,alwaysreadtheinstalla(oninstruc(ons

thatcomewiththedevice.Neverapplyforcetotryandconnectanyplug/device.


CONCLUSION:BestPrac>cesandDosandDon’ts

q  Whenfipng/handlingprocessoronmotherboardalwaysweargloves

q  Always choose to shut down you computer by clicking shutdown. Avoid switching of thepowerdirectlyfromthemainswitch.

q  If electrical power is lost, switch off all computer devices from the mains to avoid anyproblemsduetopowersurge.

q  Always“eject“USBdevicesfromtheopera(ngsystembeforedisconnec(ngthem.

q  Upgradethean(-virusregularly.

q  AlwaysuseUPS(uninterrup(blePower supply)-Thiswill keepyour computer fromcrashingduring power outages, and will protect your computer from low and high voltageoccurrences.

•  Uninstallsocwareby

–  “Add/RemoveProgram”func(oninControlPanel

–  uninstallfunc(onofapplica(ons


CONCLUSION:BestPrac>cesandDosandDon’ts…

q  Backupdata,ifpossible,beforemakingchanges.

q  ChecktoensurethatspeakersisnotmutedthroughtheControlPanel

q  MaintainingtheBa\eryforyourLaptop

Most laptop ba]eries will last at least four hours when fully charged. If notmaintained,

however,theba]erywillrequirechargingmorefrequently.formaximumperformance.

Usetheba]eryasyourpowersourceun(lthelowba]erywarningemerges.

UsingyourlaptopwiththeACadapterpluggedintoanelectricaloutletwilloverchargethe

ba]ery.Overchargingdecreasesthelifeoftheba]ery.Eventuallytheba]erywillbeunable

toholdachargeandwillrequireareplacement.

Condi>ontheba\eryformaximumperformance

1.  Dischargetheba]ery–usetheba]eryun(lthelowba]erywarningemerges.

2.  Chargetheba]ery–usetheACadapterun(ltheba]eryisfullycharged.

3.  Then immediately disconnect the AC adapter from the notebook. The procedure above

insuresbothmaximumperformanceandlonglifefortheba]ery


ThankyouandGodBlessyouall.


Documents

COMPUTER HARDWARE REPAIRS AND MAINTENANCE · COMPUTER HARDWARE REPAIRS AND MAINTENANCE Presentaon By Akusa Peter Aker Assistant Chief Programme Analyst Na#onal Judicial Instute, Abuja