CompTIA A+ Essentials AL MA perating Systems and Chapter 3 n O Software D Chapter 4 n Networking TE Chapter 5 n Security GH Chapter 6 n Operational Procedure RI TE roubleshooting, Repair, and Chapter 2 n T Maintenance PY I RI Chapter 1 n Hardware CO Part
Chapter 1 Hardware CompTIA A+ Essentials Exam Objectives Covered in This Chapter: ÛÛ 1.1 Categorize storage devices and backup media NN FDD NN HDD NN NN Optical drives NN NN Solid state vs. magnetic CD / DVD/ RW / Blu-Ray Removable storage NN Tape drive NN Solid state (e.g. thumb drive, flash, SD cards, USB) NN External CD-RW and hard drive NN Hot swappable devices and non-hot swappable devices ÛÛ 1.
NN NN Modem NN PS/2 Memory slots NN RIMM NN DIMM NN SODIMM NN SIMM NN Processor sockets NN Bus architecture NN Bus slots NN NN PCI NN AGP NN PCIe NN AMR NN CNR NN PCMCIA PATA NN IDE NN EIDE NN SATA, eSATA NN Contrast RAID (levels 0,1,5) NN Chipsets NN BIOS/ CMOS / Firmware NN ÛÛ 1.
NN Voltage selector switch NN Pins (20,24) ÛÛ 1.4 Explain the purpose and characteristics of CPUs and their features NN Identify CPU types NN AMD NN Intel NN Hyperthreading NN Multi core NN NN Dual core NN Triple core NN Quad core Onchip cache NN L1 NN L2 NN Speed (real vs. actual) NN 32 bit vs. 64bit ÛÛ 1.5 Explain cooling methods and devices NN Heat sinks NN CPU and case fans NN Liquid cooling systems NN Thermal compound ÛÛ 1.
NN Parity vs. non-parity NN ECC vs. non-ECC NN Single sided vs. double sided NN Single channel vs. dual channel NN Speed NN PC100 NN PC133 NN PC2700 NN PC3200 NN DDR3-1600 NN DDR2-667 ÛÛ 1.7 Distinguish between the different display devices and their characteristics NN Projectors, CRT and LCD NN LCD technologies NN NN NN Resolution (e.g.
ÛÛ 1.8 Install and configure peripherals and input devices NN Mouse NN Keyboard NN Bar code reader NN Multimedia (e.g. web and digital cameras, MIDI, microphones) NN Biometric devices NN Touch screen NN KVM switch ÛÛ 1.9 NN NN NN NN Summarize the function and types of adapter cards Video NN PCI NN PCIe NN AGP Multimedia NN Sound card NN TV tuner cards NN Capture cards I/O NN SCSI NN Serial NN USB NN Parallel Communications NN NIC NN Modem ÛÛ 1.
NN NN NN Communications connections NN Bluetooth NN Infrared NN Cellular WAN NN Ethernet NN Modem Power and electrical input devices NN Auto-switching NN Fixed input power supplies NN Batteries Input devices NN Stylus / digitizer NN Function keys NN Point devices (e.g. touch pad, point stick / track point) ÛÛ 1.11 Install and configure printers NN Differentiate between printer types NN Laser NN Inkjet NN Thermal NN Impact NN Local vs.
This chapter covers a lot of material—in fact, it could easily be a book in and of itself. One of the things that CompTIA is notorious for is having overlap between domains and exams, and the A+ is no exception. This domain is weighted at 27 percent (the highest of any) of the Essentials exam, and a great deal of the material covered here also appears in other domains (not to mention in the Practical Application exam).
Chapter 1 n Hardware Throughout this chapter, you will need to know about key component categories: storage devices, motherboards, power supplies, processor/CPUs, memory, display devices, input devices, adapter cards, ports and cables, and cooling systems. The first of these is discussed in the section that follows. F i g u r e 1 .1 Typical PC components Power supply System board Expansion card slot Drive bays 3.
Identify Principles of Personal Computer Storage 11 Prior to 31⁄2 ˝ disks, the most popular were 5¼˝, but these went the way of the dodo bird. Hard Disk Systems Hard disks reside inside the computer (usually) and can hold more information than other forms of storage.
Chapter 1 n Hardware rewritable media. Bonus View, the minimum required standard since 2007, is also known as Profile 1.1. BD-Live, which is basically 1.1 with an Internet connection, is called Profile 2.0. In the official specification, as noted on the Blu-ray Disc Association website (http://us.blu-raydisc.com/), the “r” is lowercase. CompTIA favors the uppercase “R.” The current capacity a Blu-ray disc can hold is 50GB with 400GB on the horizon, and an aim for 1TB by 2013.
Identify Principles of Personal Computer Storage 13 F i g u r e 1 . 2 CompactFlash and SD cards together with a reader F i g u r e 1 . 3 Three thumb drives shown with a pack of gum External Drives A number of vendors are now making external hard drives. These often connect to the computer through the USB port, but can also connect through the network (and be shared by other users) or other connections.
Chapter 1 n Hardware While not as common as they once were, Iomega’s Zip and Jaz drives are detachable, external hard disks that are used to store a large volume (around 100MB for the Zip, 1GB and 2GB for the Jaz) of data on a single, thick floppy-sized disk. The drives connect to either a parallel port or a special interface card. The major use of Zip and Jaz drives is to transport large amounts of data from place to place. This used to be accomplished with several floppies.
Identifying Motherboards 15 In order to play movies, a DVD drive must have MPEG-decoding capability. This is usually accomplished via an expansion board, but it may be built into the video card or sound card, or it may be a software decoder. If DVD data discs will play but movies won’t, suspect a problem with the MPEG decoding.
Chapter 1 n Hardware F i g u r e 1 . 4 A typical system board RAM CPU Ports Expansion slots Integrated Components Some motherboards have some of the peripheral devices built in, such as video, sound, and/or networking. These are referred to as integrated system boards. Such boards are cost-effective because they don’t require a separate video card, sound card, and so on.
Identifying Motherboards 17 F i g u r e 1 . 5 Components on a motherboard IDE connectors Floppy connector PCI slots Battery RAM Power supply connector ISA slot CPU Keyboard and mouse ports AGP slot USB ports COM and LPT ports BIOS chip Memory Slots Memory, or RAM, slots contain the memory chips. There are many and varied types of memory for PCs today. We’ll further discuss memory later in this chapter. PCs use memory chips arranged on a small circuit board.
Chapter 1 n Hardware F i g u r e 1 . 6 Various memory module form factors 30-pin SIMM (3.5 x .75") 72-pin SIMM (4.25 x 1") 168-pin DIMM (5.375 x 1") 144-pin SoDIMM (2.625 x 1") 72-pin SoDIMM (2.375 x 1") The CPU slot can take on several different forms. In the past, the CPU slot was a rectangular box called a PGA socket, with many small holes to accommodate the pins on the bottom of the chip.
Identifying Motherboards 19 Ta b l e 1 .
Chapter 1 n Hardware Power Connectors A power connector allows the motherboard to be connected to the power supply. On an ATX, there is a single power connector consisting of a block of 20 holes (in two rows). On an AT, there is a block consisting of 12 pins sticking up; these pins are covered by two connectors with six holes each. Figure 1.8 shows a very versatile motherboard that happens to have both kinds, so you can compare. The upper connector is for ATX, and the lower one is for AT.
Identifying Motherboards 21 Your PC stores the settings in a special memory chip called the CMOS chip. To retain these settings, the CMOS chip requires power constantly. To prevent the CMOS chip from losing its charge, a small battery is located on the motherboard. The CMOS chip holds the BIOS. System Board Form Factors Form factor refers to the size and shape of a component. Most system boards today use the ATX form factor.
Chapter 1 n Hardware One case may also be distinguished from another in terms of its orientation. A desktop case lies with its widest side flat on the desk; a tower case stands up on end. Finally, one case differs from another in terms of the number of drive bays it has. For example, within the broad category of tower cases are mini-towers (typically with two large and two small drive bays), mid-towers, and full towers (typically with four large and three small drive bays).
Identifying Motherboards 23 ATX Most system boards today use the ATX (Advanced Technology Extended) form factor. It provides many design improvements over the AT, including I/O ports built directly into the side of the motherboard, the CPU positioned so that the power-supply fan helps cool it, and the ability for the PC to be turned on and off via software. It uses a PS/2-style connector for the keyboard. The expansion slots are parallel to the narrow edge of the board. See Figure 1.11. F i g u r e 1 .
Chapter 1 n Hardware of system resources. USB 1.1 runs at 12Mbps, and USB 2.0 runs at 480Mbps. Because USB is a serial interface, its width is 1 bit. IEEE 1394/FireWire Some newer motherboards have a built-in IEEE 1394/FireWire port, although this port is more typically found on a PCI expansion board. It transfers data at 400Mbps and supports up to 63 chained devices on a single set of resources. It’s hot-pluggable, like USB. Figure 1.12 shows the connections on a FireWire card. F i g u r e 1 .
Identifying Motherboards 25 Physical Memory Physically, memory or RAM is a collection of integrated circuits that store data and program information as patterns of 1s and 0s (on and off states) in the chip. Most memory chips require constant power (also called a constant refresh) to maintain those patterns of 1s and 0s. If power is lost, all those tiny switches revert back to the off position, effectively erasing the data from memory. Some memory types, however, don’t require a refresh.
Chapter 1 n Hardware Double Data Rate (DDR) SDRAM/DDR2 Essentially, clock-doubled SDRAM. The memory chip can perform reads and writes on both sides of any clock cycle (the up, or start, and the down, or ending), thus doubling the effective memory executions per second. So, if you’re using DDR SDRAM with a 100MHz memory bus, the memory will execute reads and writes at 200MHz and transfer the data to the processor at 100MHz.
Identifying Motherboards 27 F i g u r e 1 .1 3 Single inline memory modules (SIMMs) 30-pin SIMM 72-pin SIMM F i g u r e 1 .1 4 Dual inline memory module (DIMM) A RIMM (Rambus inline memory module) is just like a DIMM, except it’s a Rambus DRAM stick, has 184 pins, and is slightly longer in size. SoDIMMs and MicroDIMMs Portable computers (notebooks and subnotebooks) require smaller sticks of RAM because of their smaller size.
Chapter 1 n Hardware RAM Banks and Bit Width As explained earlier, 30-pin SIMMs are 8-bit, 72-pin SIMMs are 32-bit, and DIMMs are 64-bit. The motherboard has an address bus that carries data from the RAM to the CPU and chipset. It has a certain width. On Pentium and higher systems, it’s 64-bit; on earlier systems, it’s 32-bit (386 and 486) or less (286 and below). A bank of RAM is a single stick or a group of sticks where the collective bit width adds up to the width of the address bus.
Identifying Motherboards 29 External Speed (Clock Speed) The clock speed, or external speed, is the speed at which the motherboard communicates with the CPU. It’s determined by the motherboard, and its cadence is set by a quartz crystal (the system crystal) that generates regular electrical pulses. Internal Speed The internal speed is the maximum speed at which the CPU can perform its internal operations.
Chapter 1 n Hardware Instruction Set The motherboard’s chipset contains an instruction set for communicating with the CPU; the CPU must understand the commands in that set. For example, a mother board designed for an AMD Athlon CPU can’t accept an Intel Pentium CPU, because the instruction set is different. Voltage The CPU requires that a certain voltage of power be supplied to it via the mother board’s interface. This can be anywhere from +5V for a very old CPU down to around +2.
Identifying Motherboards 31 Third-generation (MMX) Pentiums, released in 1997, added multimedia extensions (MMX) to help the CPU work with graphic-intensive games. They used Socket 7 sockets, drew +2.8V, and ran at 166MHz to 233MHz. Due to the voltage difference between the Pentium MMX CPU and other Socket 7 CPUs, the MMX CPU required a motherboard that either was specifically for that CPU or had a VRM that could take the voltage down to that level.
Chapter 1 n Hardware certain aspects outperformed its more expensive counterpart. Intel has also named its lowbudget Pentium III CPUs Celeron. The Celeron CPU has come in several package types, including a 370-pin PGA socket (Socket 370) and an SECC variant called single-edge processor (SEP) that is similar to the circuit board inside an SECC cartridge but without the plastic outer shell.
Identifying Motherboards 33 Processors were also created for the server market, but you are not required to know of them for this exam. The Itanium chip is one of the most notable: it came out in 2001 and was geared toward high-end servers. Ta b l e 1 . 3 The Intel Family of Processors Chip Year Added Data Bus Width (in Bits) Address Bus Width (in Bits) Speed (in MHz) 8080 1974 8 8 2 8086 1978 16 20 5–10 8088 1979 8 20 4.
Chapter 1 n Hardware A Pentium 4 Extreme Edition was released in 2003. Featuring a dual-core processor as its biggest modification over the Pentium 4, it was targeted for the gaming user. Ta b l e 1 . 4 Physical Characteristics of Pentium-Class Processors Processor Speeds (MHz) Socket Pins Voltage Pentium-P5 (first generation) 60–66 4 273 +5V Pentium-P54C (second generation) 75–200 5 or 7 296 +3.3V Pentium-P55C (third generation) 166–233 7 321 +2.
Identifying Motherboards 35 Some newer systems also have an L3 cache, which is an external cache on the motherboard that sits between the CPU and RAM. IDE and SCSI On-Motherboard Interfaces Most motherboards include two integrated drive electronics (IDE) channels but don’t include built-in Small Computer System Interface (SCSI). A consideration when choosing a motherboard for IDE is that it needs to support the desired level of UltraDMA to match the capabilities of the hard drive you want to use.
Chapter 1 n Hardware (depending on the system). Another name for this setup program is CMOS Setup. The most common settings to adjust in CMOS include port settings (parallel, serial, USB), drive types, boot sequence, date and time, and virus/security protections. Accessing CMOS Setup Your PC keeps these settings in a special memory chip called the Complementary Metallic Oxide Semiconductor (CMOS) chip. The CMOS chip must have a constant source of power to keep its settings.
Identifying Motherboards 37 Ports and Peripherals In CMOS Setup, you can enable or disable integrated components, such as built-in video cards, sound cards, or network cards. You may disable them in order to replace them with different models on expansion boards, for example. You can also disable the on-board I/O ports for the motherboard, including parallel, serial, and USB.
Chapter 1 n Hardware HDD Auto Detection Some CMOS Setup programs have a feature that polls the IDE channels and provides information about the IDE devices attached to them. You can use this feature to gather the settings for a hard disk. However, most hard disks these days are fully Plug and Play, so they automatically report themselves to the CMOS Setup. Drive Configuration You can specify how many floppy drives are installed and what types they are. Floppy drives aren’t automatically detected.
Identifying Motherboards 39 If you make a mistake in the upgrade process, the computer can become unbootable. If this happens, your only option may be to ship the box to a manufacturer-approved service center. Be careful! Post Routines Every computer has a diagnostic program built into its BIOS called the power-on self-test (POST). When you turn on the computer, it executes this set of diagnostics.
Chapter 1 n Hardware Accelerated Graphics Port (AGP); they’re for circuit boards. External expansion buses include serial, parallel, Universal Serial Bus (USB), FireWire, and infrared. The following sections explain some of the most common buses. There are many obsolete bus types, including Video Electronics Standards Association Local Bus (VESA local bus, or VL-Bus), Microchannel Architecture (MCA), and enhanced ISA (EISA).
Identifying Motherboards 41 AGP (Accelerated Graphics Port) As systems got faster, PC game players wanted games that had better graphics, more realism, and more speed. However, as the computers got faster, the video technology couldn’t seem to keep up, even with the PCI bus. The AGP bus was developed to meet this need. The AGP slot is usually brown, and there is only one. It’s a 32-bit or 64-bit bus, and it runs very fast (66MHz or faster). It’s used exclusively for the video card.
Chapter 1 n Hardware PCMCIA (Personal Computer Memory Card International Association) The PCMCIA standard defines the PC Card (formerly known as the PCMCIA Card), an interface designed for laptop computers. This standard is discussed in more detail later in this chapter. Legacy Parallel and Serial These buses are called legacy because they’re old technology and are being phased out. The legacy serial port, also called an RS-232 port, is a 9-pin or 25-pin male connector.
Identifying Motherboards 43 ATA-6 supports UltraDMA/100, with transfer modes of up to 100Mbps. If an ATA-5 or ATA-6 drive is used with a normal 40-wire cable or is used on a system that doesn’t support the higher modes, it reverts to the ATA-4 performance level. ATA-7 supports UltraDMA/133, with transfer modes of up to 150Mbps and serial ATA (discussed later). ATA-8 made only minor revisions to ATA-7 and also supports UltraDMA/133, with transfer modes of up to 150Mbps and serial ATA.
Chapter 1 n Hardware F i g u r e 1 .17 Master/slave jumpers J8 3 5 J8 1 Single drive (standard installation) 6 4 5 J8 3 2 For two drives J8 1 Drive 1: master 6 4 J8 3 5 2 J8 1 Drive 2: slave 6 4 2 Most BIOS Setup programs today support Plug and Play, so they detect the new drive automatically at startup. If this doesn’t work, the drive may not be installed correctly, the jumper settings may be wrong, or the BIOS Setup may have the IDE interface set to None rather than Auto.
Identifying Motherboards 45 However, if the problem is a bad disk drive, the symptoms aren’t as obvious. As long as the BIOS POST routines can communicate with the disk drive, they’re usually satisfied. But the POST routines may not uncover problems related to storing information. Even with healthy POST results, you may find that you’re permitted to save information to a bad disk, but when you try to read it back, you get errors.
Chapter 1 n Hardware RAID 5 Combines the benefits of both RAID 0 and RAID 1, and is known as Striping with Parity. It uses a parity block distributed across all the drives in the array, in addition to striping the data across them. That way, if one drive fails, the parity information can be used to recover what was on the failed drive. A minimum of three drives is required. Firmware Any software that is built into a hardware device is called firmware.
Identifying Motherboards 47 Exam Essentials Know what the BIOS does. This is a ROM chip on the motherboard. It contains the BIOS software that tells the processor how to interact with the hardware in the computer. The BIOS chip tells the motherboard how to start up, check itself and its components, and pass off control to the operating system. Know the different types of memory. DRAM is dynamic random access memory. SRAM is static random access memory.
Chapter 1 n Hardware Working with Power Supplies Power-supply problems are usually among the ones that are easy to troubleshoot: If the system doesn’t respond in any way when the power is turned on or you are experiencing randomly frying parts, or an incredibly annoying sound, open the case, remove the power supply, and replace it with a new one. Critical Information The device in the computer that provides the power is the power supply.
Working with Power Supplies 49 As a general rule, you should have a large enough power supply for all the slots in the computer with the most likely devices that will be installed. In other words, you should calculate the power-supply capacity from what is possible and not just what is currently on the motherboard. Ta b l e 1 .
Chapter 1 n Hardware A 20-pin main connector from the power supply to the motherboard is standard for all ATX power supplies. In addition to this connector, many will include an auxiliary power connector of either 4 or 6 pins to provide additional power. In 2004, the ATX12V 2.0 standard was passed, changing the main connector from 20 pins to 24. The additional pins provide +3.3V, +5V, and +12V (the fourth pin is a ground) for use by PCIE cards.
Cooling Methods 51 be more difficult for an untrained technician to work on, but they result in an almost completely silent system. Cooling Issues A PC that works for a few minutes and then locks up is probably experiencing overheating due to a heat sink or fan not functioning properly. To troubleshoot overheating, first check all fans inside the PC to ensure they’re operating, and make sure any heat sinks are firmly attached to their chips.
Chapter 1 n Hardware Exam Essentials Learn to troubleshoot overheating issues. When overheating occurs, you need to be able to isolate the source quickly and respond before the problem affects internal system components. Identify problems that can result from overheating. Overheating can cause spontaneous rebooting or shutdown. Overheating is often caused by nonfunctioning cooling fans or improper airflow through the PC.
Display Devices 53 Digital Video Interface (DVI) There are several types of DVI pin configurations, but all connectors are D-shaped. The wiring differs based on whether the connector is single-linked or dual-linked (extra pins are used for the dual link). DVI differs from everything else in that it includes both digital and analog signals at the same time, which makes it popular for LCD and plasma TVs. Figure 1.19 shows a DVI connector. F i g u r e 1 .
Chapter 1 n Hardware Display resolutions include the following, which you must know for the A+ Essentials exam: XGA Extended graphics array has been around since 1990. It’s a 1024×768 resolution that offers fixed-function hardware acceleration for 2D tasks. SXGA+ Super extended graphics array is a 1400 ×1050 resolution commonly used on 14or 15-inch laptops. It’s typically considered the maximum resolution that video projectors will work with.
Display Devices 55 The creation of the image is known as a raster. Rasterizing an image, thus, is creating the image in such a way that it can be displayed in a rectangular ray. Display System Problems There are two types of video problems: no video and bad video. No video means no image appears on the screen when the computer is powered up. Bad video means the quality is substandard for the type of display system being used. No Video Any number of things can cause a blank screen.
Chapter 1 n Hardware Upgrading Display Devices Before connecting or disconnecting a monitor, ensure that the power to both the PC and the monitor is off. Then, connect a VGA (DB-15) cable from the monitor to the PC’s video card, and connect the monitor’s power cord to an AC outlet. Other than the power supply, one of the most dangerous components to try to repair is the monitor, or CRT monitor. I recommend that you not try to repair monitors.
Input and Peripheral Devices 57 Be able to determine the cause of display system problems. The most common display problems relate to power, brightness, or contrast. Adjusting the monitor controls should be your first step when troubleshooting. Input and Peripheral Devices A virtually unlimited number of types of input devices can be connected to a PC.
Chapter 1 n Hardware Remember that most of the dollars spent on systems are for labor. If you spend an hour cleaning a $12.00 keyboard, then you have probably just cost your company $20.00. Knowing how to fix certain things doesn’t necessarily mean that you should fix them. Always evaluate your workload, the cost of replacement, and the estimated cost of the repair before deciding on a course of action.
Input and Peripheral Devices 59 Adapter cards are purchased to match an available expansion slot in the motherboard. PCI is the most common type of expansion slot for an adapter card in today’s PCs. ISA slots are nearly obsolete, and AGP slots are used only for video cards. Expansion slots are used to install various devices in the computer to expand its capabilities. Some expansion devices that may be installed in these slots include video, network, sound, and disk interface cards.
Chapter 1 n Hardware Sound-Card Problems Sound cards are traditionally one of the most problem-ridden components in a PC. They demand a lot of PC resources and are notorious for being inflexible in their configuration. The most common problems related to sound cards involve resource conflicts (IRQ, DMA, or I/O address). The problem is much less pronounced on PCI than on ISA cards. Luckily, most sound-card vendors are aware of the problems and ship very good diagnostic utilities to help resolve them.
Input and Peripheral Devices 61 Bits of Data Simultaneously Conveyed A serial cable carries only one bit at a time. A parallel cable carries multiple bits at a time (usually eight). Data Transmission Speed This is expressed in kilobits or megabits per second and refers to the overall data throughput.
Chapter 1 62 n Hardware PS/2 (Mini-DIN) A round connector with six small pins inside, commonly used to connect keyboards on ATX motherboards or PS/2 style mice. DIN A larger round connector with five rather large pins inside, used for connecting the keyboard on an AT motherboard. USB A flat rectangular connector, used with USB interfaces. Cabling Cables are used to connect two or more entities together. They’re usually constructed of several wires encased in a rubberized outer coating.
Input and Peripheral Devices 63 One cable that deserves special mention is the null modem cable. It allows two computers to communicate with each other without using a modem. This cable has its transmit and receive wires crossed at both ends, so when one entity transmits on its TD line, the other entity receives it on its RD line. Unshielded twisted pair (UTP) is the most common type of cable used for network cabling.
Chapter 1 n Hardware Principles of Laptops and Portable Devices Whether you choose to call them laptops, portable devices, or something different is mostly a matter of semantics. This objective tests your knowledge of some of the basic operations of laptops. In many cases, the components are the same as in a desktop computer, and they were discussed already. We’ll focus now on those that are different.
Principles of Laptops and Portable Devices 65 Because different hardware is available in docked versus undocked configurations, you may want to set up hardware profiles in Windows to account for the differences. Autoswitching and Fixed Input Autoswitching power supplies allow you to use the same supply for more than one voltage. Most autoswitching power supplies can operate on voltages from 100 to 240, allowing them to be used in countries almost anywhere in the world.
Chapter 1 n Hardware Depending on the notebook model, the battery may be anywhere, but it’s usually under the keyboard. On some models, you can slide the battery out the side by removing a panel or cover; on other models, you must lift the keyboard. Pull out the battery, and insert a fresh battery in the same slot, pressing it firmly into place. Then, replace the cover over the battery’s bay.
Principles of Laptops and Portable Devices 67 Pointing and Input Devices Pointing devices with laptops include such options as touchpads, point sticks, and track points. Some laptops come with only one of these, whereas others include a combination; and users can always opt for something else (such as a wireless mouse). Which you use is more a matter of preference and comfort than anything else. Input devices can include a stylus, or digitizer.
Chapter 1 n Hardware At least 10 power schemes are possible, including Home/Office Desk (which doesn’t use power management), Portable/Laptop (the default on a laptop PC), Always On, Max Battery, and so on. From the Advanced tab, you can choose what happens when you close the lid, when you press the power button, and when you press the sleep button.
Principles of Laptops and Portable Devices 69 Disassembling a Notebook PC There are many designs of notebook PC cases, and each one disassembles a little differently. The best way to determine the proper disassembly method is to consult the documentation from the manufacturer. Some models of notebook PCs require a special T-8 Torx screwdriver.
Chapter 1 n Hardware Exam Essentials Know the different types of PCMCIA cards. PCMCIA cards are the expansion cards for notebook PCs. Most notebook PCs have a PCMCIA bay that can accept one Type III device or two Type I or Type II devices. Know the different monitor resolutions. The exam expects you to know four different types: XGA, SXGA+, UXGA, and WUXGA. Know the resolution for each of them. Know the purpose of the Fn key.
Installation and Configuration of Printers 71 This section provides details about various technologies of printers. These printers may be differentiated from one another in several ways, including the following: Impact vs. Nonimpact Impact printers physically strike an inked ribbon and therefore can print multipart forms; nonimpact printers deliver ink onto the page without striking it. Dot matrix is impact; everything else is nonimpact. Continuous Feed vs.
Chapter 1 n Hardware Dot-matrix printers are still found in many warehouses, and other businesses, where multipart forms are used. Ink-Jet Printers Ink-jet printers are one of the most popular types in use today. This type of printer sprays ink on the page to print text or graphics. It’s a nonimpact, sheet-fed line printer. Figure 1.24 shows an ink cartridge. Some cartridges, like this one, contain the printhead for that color of ink; you get a new printhead each time you replace the cartridge.
Installation and Configuration of Printers 73 Parts of a Laser Printer An electrophotographic laser printer consists of the following major components: Printer Controller A large circuit board that acts as the motherboard for the printer. It contains the processor and RAM to convert data coming in from the computer into a picture of a page to be printed. Toner Cartridge and Drum A powdery mixture of plastic resin and iron oxide.
Chapter 1 n Hardware F i g u r e 1 . 2 6 The EP laser scanning assembly (side view and simplified top view) SIDE VIEW Laser beam Mirror Laser assembly EP drum Laser scanning assembly Laser beam Direction of rotation Fixed mirror Rotating mirror Paper Transport Assembly Moves the paper through the printer. The paper transport assembly consists of a motor and several rubberized rollers. These rollers are operated by an electronic stepper motor. See Figure 1.27 for an example.
Installation and Configuration of Printers 75 F i g u r e 1 . 2 8 The transfer corona assembly Print drum EP cartridge Toner Paper Transfer corona wire Static eliminator strip DC Power Supply Delivers lower voltages to components in the printer that need much lower voltages than the corona wires do (such as circuit boards, memory, and motors). Fusing Assembly Melts the plastic resin in the toner so that it adheres to the paper.
Chapter 1 n Hardware F i g u r e 1 . 3 0 The cleaning step of the EP process Cleaning blade Used toner Print drum Used toner hopper The actual amount of toner removed in the cleaning process is quite small. The cartridge will run out of toner before the used toner receptacle fills up. Step 2: Conditioning In the conditioning step (Figure 1.
Installation and Configuration of Printers 77 F i g u r e 1 . 3 2 The writing step of the EP process EP drum Laser scanning assembly Laser beam Direction of rotation Fixed mirror Rotating mirror Step 4: Developing Now that the surface of the drum holds an electrical representation of the image being printed, its discrete electrical charges need to be converted into something that can be transferred to a piece of paper. The EP process’s developing step accomplishes this (Figure 1.33).
Chapter 1 n Hardware The photosensitive drum now has toner stuck to it where the laser has written. The photosensitive drum continues to rotate until the developed image is ready to be transferred to paper in the next step. Step 5: Transferring At this point in the EP process, the developed image is rotating into position. The controller notifies the registration rollers that the paper should be fed through.
Installation and Configuration of Printers 79 F i g u r e 1 . 3 5 The fusing step of the EP process Fusing roller Pressure roller Putting It All Together Figure 1.36 summarizes all the EP process printing steps. First, the printer uses a rubber scraper to clean the photosensitive drum. Then the printer places a uniform, negative, –600VDC charge on the photosensitive drum by means of a charge corona.
Chapter 1 n Hardware The LED printing process uses a row of small LEDs very close to the drum to expose it. Each LED is about the same size as the diameter of the laser beam used in a laser printer. Except for the writing stage, the operation is the same as the laser printing process. LED printers are cheaper and smaller than lasers. However, they’re considered lower-end printers, and they have a lower maximum dots per inch (dpi)—under 800dpi versus 1200 or more for a laser printer.
Installation and Configuration of Printers 81 with printer port. It sends data 8 bits at a time (in parallel) and uses a cable with a male DB-25 connector at the computer and a 36-bin Centronics male connector at the printer. Its main drawback is its cable length, which must be less than 10 feet. Universal Serial Bus (USB) The most popular type of printer interface as this book is being written is the USB. It’s the most popular interface for just about every peripheral.
Chapter 1 n Hardware F i g u r e 1 . 3 7 Configure the advanced options. F i g u r e 1 . 3 8 Configure the tray and other settings.
Exam Essentials 83 Exam Essentials Know the common types of printers. Know and understand the types of printers, such as impact printers, ink-jet printers, and laser printers (page printers), as well as their interfaces and print media. Know the fundamentals of scanners. be thought of as input devices. Whereas printers are output devices, scanners can Understand the process of printing for each type of printer. Each type of printer puts images or text on paper.
Chapter 1 n Hardware Review Questions 1. What two types of expansion slots are found on all modern motherboards? What is a third, older type that might or might not also be present? 2. Name three features that distinguish an ATX motherboard from an AT motherboard. 3. What are PGA and SECC? Which of those types is the Socket 423 used with the Pentium 4? 4. What voltages does a typical power supply provide to the motherboard? 5.
Answers to Review Questions 85 Answers to Review Questions 1. PCI and AGP. The third type is ISA. 2. Possible answers include: (1) position of CPU, (2) expansion slot orientation, (3) built-in ports on the side, (4) one-piece power supply connector, (5) physical size and shape of the motherboard, and (6) type of keyboard connector. 3. They are the two types of slots/sockets for CPUs in motherboards. PGA is the type with a grid of holes into which pins fit on a flat chip.
