1. © 2008 Cisco Systems, Inc. All rights reserved.Cisco ConfidentialPresentation_ID 1 Chapters 1-4: IT Essentials IT Essentials 5.0

2. Presentation_ID 2 © 2008 Cisco Systems, Inc. All rights reserved.Cisco Confidential ROM and RAM  Read-only memory (ROM)  Basic instructions for booting the computer and loading the operating system are stored in ROM.  ROM chips retain their contents even when the computer is powered down.  Random-access memory (RAM)  RAM is temporary storage for data and programs that are being accessed by the CPU.  RAM is volatile memory, which means that the contents are erased when the computer is powered off.  More RAM means more capacity to hold and process large programs and files, as well as enhance system performance.

3. Presentation_ID 3 © 2008 Cisco Systems, Inc. All rights reserved.Cisco Confidential Cache and Error Checking  Cache SRAM is used as cache memory to store the most frequently used data. SRAM provides the processor with faster access to the data than retrieving it from the slower DRAM, or main memory.  Error Checking Memory errors occur when the data is not stored correctly in the RAM chips. The computer uses different methods to detect and correct data errors in memory Nonparity Parity ECC

4. Presentation_ID 4 © 2008 Cisco Systems, Inc. All rights reserved.Cisco Confidential Adapter Cards  Adapter cards increase the functionality of a computer by adding controllers for specific devices or by replacing malfunctioning ports.  Examples of adapter cards: Sound adapter and video adapter USB, parallel, and serial ports Network Interface Card (NIC), wireless NIC, and modem adapter  Types of expansion slots: Peripheral Component Interconnect (PCI) Advanced Graphics Port (AGP) PCI-Express Mini PCI (laptops)

5. Presentation_ID 5 © 2008 Cisco Systems, Inc. All rights reserved.Cisco Confidential Storage Drives  Storage drives read or write information to magnetic storage media.  They may be fixed or removable.  The hard disk drive (HDD) is a magnetic storage device. The storage capacity is measured in gigabytes (GB) or terabytes (TB)  Magnetic hard drives have drive motors designed to spin magnetic platters and move the drive heads.  Solid state drives (SSDs) do not have moving parts, which results in faster access to data, higher reliability, reduced power usage.  A floppy disk drive (FDD) is storage device that uses removable 3.5 inch floppy disks that can store up to 1.44 MB of data.

6. Presentation_ID 6 © 2008 Cisco Systems, Inc. All rights reserved.Cisco Confidential RAID Levels  RAID provides a way to store data across multiple hard disks for redundancy. RAID Level Min # of Drives Description 02Data striping without redundancy 12Disk mirroring 22Error-Correcting Coding 33Byte-level data striping with dedicated parity 43Block-level data striping with dedicated parity 53Block-level data striping with distributed parity 64Independent Data Disks with Double Parity 0/14Combination of data striping and mirroring 104Mirrored set in a striped set

7. Presentation_ID 7 © 2008 Cisco Systems, Inc. All rights reserved.Cisco Confidential Video Ports and Cables  A video port connects a monitor cable to a computer. Video ports and connector types: DVI, Displayport, RCA, DB-15, BNC, RJ-45, MiniHDMI, Din-6  Display cables transfer video signals from the computer to display devices. Display cable types: High-Definition Multimedia Interface (HDMI), DVI, Video Graphics Array (VGA), Component/RGB, Composite, S-Video, Coaxial, Ethernet,

8. Presentation_ID 8 © 2008 Cisco Systems, Inc. All rights reserved.Cisco Confidential Ports and Cables  Serial ports transmit one bit of data at a time.  A telephone cable (RJ11) is used to connect a modem to a telephone outlet.  USB is a standard interface for connecting hot-swappable peripheral devices to a computer. Some devices can also be powered through the USB port.  FireWire is a high-speed, hot-swappable interface that can support up to 63 devices. Some devices can also be powered through the FireWire port.  A parallel cable is used to connect parallel devices, such as a printer or scanner, and can transmit 8 bits of data at one time.

9. Presentation_ID 9 © 2008 Cisco Systems, Inc. All rights reserved.Cisco Confidential Input Devices  Input devices are used to enter data or instructions into a computer: Mouse and Keyboard KVM switch Gamepad and joystick Digital camera and digital video camera Biometric authentication device Touch screen Scanner

10. Presentation_ID 10 © 2008 Cisco Systems, Inc. All rights reserved.Cisco Confidential Selecting RAM  New RAM may be needed when an application locks up or the computer displays frequent error messages  When selecting new RAM, check the compatibility with the current motherboard.  The speed of the new RAM must be the same or faster than the existing RAM.

11. Presentation_ID 11 © 2008 Cisco Systems, Inc. All rights reserved.Cisco Confidential Selecting Adapter Cards  Adapter (or expansion) cards add extra functionality to a computer. Before purchasing an adapter card, check: Is there an open expansion slot? Is the adapter card compatible with the open slot? What are the customer’s current and future needs? What are the possible configuration options? If the motherboard does not have compatible expansion slots, external devices are an option: Are USB or FireWire versions of the external device available? Does the computer have an open USB or FireWire port?

12. Presentation_ID 12 © 2008 Cisco Systems, Inc. All rights reserved.Cisco Confidential Procedures to Protect the Environment  Computers and peripherals contain materials that can be harmful to the environment.  Protect the environment by responsibly disposing and recycling: Material Safety Data Sheet (MSDS): Fact sheet summarizing information about material identification, including hazardous ingredients that can affect personal health, fire hazards, and first aid requirements. Proper Disposal: Comply with policies that specify the procedures for disposing different materials such as batteries, monitors and used printer kits.

13. Presentation_ID 13 © 2008 Cisco Systems, Inc. All rights reserved.Cisco Confidential Proper Tool Use Proper use of an antistatic wrist strap can prevent ESD damage to computer components. CAUTION: Never wear an antistatic wrist strap if you are repairing a monitor or CRT. Proper use of an antistatic mat transfers static electricity away from equipment to a grounding point. Proper use of hand tools. Proper Use of Cleaning Materials. CAUTION: Before cleaning any device, turn it off and unplug the device from the power source.  Safety in the workplace is everyone's responsibility.  Before cleaning or repairing equipment, check to make sure that tools are in good condition.

14. Presentation_ID 14 © 2008 Cisco Systems, Inc. All rights reserved.Cisco Confidential Attach Components to the Motherboard  CPU on Motherboard The CPU and motherboard are sensitive to electrostatic discharge. The CPU is secured to the socket on the motherboard with a locking assembly. CAUTION: When handling a CPU, do not touch the CPU contacts.  Thermal compound Helps keep the CPU cool. To install a used CPU, clean it and the base of the heat sink with isopropyl alcohol to remove the old thermal compound.  Heat Sink/Fan Assembly The Heat Sink/Fan Assembly is a two-part cooling device. The heat sink draws heat away from the CPU.  Install RAM RAM provides temporary data storage for the CPU and should be installed in the motherboard before the motherboard is placed in the computer case.

15. Presentation_ID 15 © 2008 Cisco Systems, Inc. All rights reserved.Cisco Confidential Boot Computer for the First Time  When the computer is booted, the basic input/output system (BIOS) will perform a power-on self test (POST) to check on all of the internal components.  The BIOS contains a setup program used to configure settings for hardware devices. The configuration data is saved to a special memory chip called a complementary metal-oxide semiconductor (CMOS) or can be saved in nonvolatile memory which does not need power to retain settings.  POST checks to see that all of the hardware in the computer is operating correctly. If a device is malfunctioning, an error or a beep code alerts the technician that there is a problem.

16. Presentation_ID 16 © 2008 Cisco Systems, Inc. All rights reserved.Cisco Confidential The Purpose of Preventive Maintenance  Reduce the possibility of hardware or software problems by implementing a preventive Maintenance Plan based on at least two factors: Computer location Computer use  Benefits of Preventive Maintenance are: Reduced computer down time and repair costs. Increased data protection. Extended life of the components. Increased equipment stability.  Preventive Maintenance can be divided into: Hardware maintenance Software maintenance

17. Presentation_ID 17 © 2008 Cisco Systems, Inc. All rights reserved.Cisco Confidential The Troubleshooting Process  Follow an organized and logical procedure.  Eliminate variables one at a time.  Troubleshooting is a skill that is refined over time.  The first and last steps involve effectively communicating with the customer. StepTroubleshooting Process 1Identify the Problem 2Establish a Theory of Probable Cause 3Test the Theory to Determine Cause 4Establish a Plan of Action to Resolve the Problem and Implement the Solution 5Verify Full System Functionality and, if Applicable, Implement Preventive Measures 6Document Findings, Actions, and Outcomes