Download
1 / 140
1.41k likes | 1.59k Vues
The Complete A+ Guide to PC Repair 5/e. Chapter 9 Other Peripherals. Chapter Objectives. After completing this chapter you will be able to: Describe the components of the video subsystem Differentiate among monitor types including laptop displays Define basic monitor theory and terminology
E N D
The Complete A+ Guideto PC Repair 5/e Chapter 9Other Peripherals
Chapter Objectives • After completing this chapter you will be able to: • Describe the components of the video subsystem • Differentiate among monitor types including laptop displays • Define basic monitor theory and terminology • Describe issues regarding video memory • Install a video adapter and associated software • Perform basic video troubleshooting techniques • Explain basic printing concepts • Describe how each type of printer operates
Chapter Objectives (cont.) • Perform a printer installation, including print driver • Perform preventive printer maintenance • Control printers from Windows and make appropriate printer adjustments • Solve common printer problems • Demonstrate ethical and professional behavior when solving computer problems
Video Overview • Video quality is very important to computer users. • Users usually derive the most gratification from their monitor, although sound quality is now becoming as important. • The monitor, which displays the data, is one of the most expensive computer components. • Technicians must look at video as a subsystem that consists of the monitor, the electronic circuits that send the monitor instructions, and the cable that connects them.
Types of Video Output Devices • Video output devices such as monitors and projectors are commonly used with desktop and laptop computers. • Monitors can be classified several ways: • Color or non-color • Analog or digital signals used to produce colors • Type of video adapter used
Video Subsystem Figure 9.1
Video Output Technology CRT Cathode Ray Tube – bulky and resembles a TV. Liquid Crystal Display – used in laptops, flat panel monitors, TVs, and projectors. LCD Digital Light Processing – used in projectors and rear projection TVs. An array of mirrors used to create a light or dark pixel. A color wheel provides color. DLP
CRT Technology Terms Dot triad – three colored dots grouped to gather to form one image. 1 Pixel (picture element) – The smallest visible image on a screen. 2
Tech Tip – Recycle CRTs CRTs contain toxic substances that can cause health risks to humans if CRTs are disposed of improperly. Consider donating a CRT or using a Web site such as www.crtusedmonitors.com instead of throwing it away.
LCD Technology Terms One glass substrate is the color filter, with three main colors. The other glass substrate is the TFT (thin film transistor) array, which has the technology to direct the liquid crystal to block the light.
LCD Technology Terms A backlight (fluorescent lamp or LEDs) extends behind the combined glass assembly, and the light is always on. This is why an LCD monitor appears to sometimes glow even when it’s off and why crystals are needed to block some of the light to create the intensities of light. Liquid crystals are sensitive to temperature changes. Laptop displays may appear distorted in cold or hot temperatures due to the liquid crystals.
Flat Panel Versus CRT Monitor Figure 9.5
DLP Technology The mirrors are used to create a light or dark pixel on a projection surface by being repositioned to different angles to reflect light. A color wheel or LEDs are used for the primary colors red, green, and blue.
Type of Video Output Devices • Plasma displays work very similarly to LCDs, except that they have plasma gas in little chambers. When electricity is applied inside the chambers, excited electrons hit red, green, and blue phosphorous. • Many believe that plasma displays require less energy than CRTs. This is not necessarily true. However, LCDs do take less energy than CRTs.
Types of Video Output Devices • Touch screen monitors connect to PCs and respond to contact on the screen rather than keyboard or mouse input. • The two most common types of touch screens are resistive and capacitive. • Resistive touch screen monitors have a flexible membrane stretched over the face of the monitor. • Capacitive touch screen monitors are more durable than resistive monitors. They respond to a touch on the screen and easily detect contact.
Video Terminology and Theory • Video has unique terminology associated with it. It is important to be familiar with video terminology. • Resolution – The number of pixels shown on a monitor or the output of a printer. • Two numbers separated by an x • With 640x480 (640 “by” 480), the first number, 640, is the number of pixels that fit horizontally across the screen. • The second number, 480, describes the number of pixels that fit vertically on the screen.
Video Adapter/Monitor Types Both the monitor and the adapter have to support the higher resolutions.
Video Terminology and Theory The maximum time a CRT screen is scanned in one second. Refresh Rate Horizontal Scanning Frequency The rate at which a CRT monitor beam moves across the screen. The rate at which the monitor electron beam draws the entire screen. Vertical Scan Rate
Tech Tip • Use a 75Hz or greater refresh rate An improperly configured refresh rate can cause monitor flicker, which can lead to headaches or eye strain. Usually, a 75Hz or greater refresh rate produces less flicker.
CRT Terminology • Multi-scan Monitor – A monitor that can lock onto different vertical and horizontal scanning frequencies. • Interlacing – A scanning method used with monitors in which only the odd numbered pixel rows are scanned, followed by the even numbered pixel rows. • Degauss – A device that demagnetizes monitors. • Also called a degaussing coil.
Video Terminology and Theory • Monitors frequently have a button that allows a menu to be accessed or several buttons used to adjust the image quality. • Power – Powers the monitor off and on • Input – Available when both analog and digital (VGA and DVI) input connectors are present • Auto adjust – Automatically refines settings • Brightness – Intensity of the image or luminance of the backlight on a LCD • Contrast – Degree of difference between light and dark • Position – Adjusts the viewing area • Reset – Resets to default settings
LCD (Liquid Crystal Display) • LCD is a video technology used with laptops and flat screen monitors that are powered by a low-voltage DC power source. • They are more reliable and have a longer life span than CRT monitors. • There are two basic types of LCD: passive matrix and active matrix.
LCDs • Passive matrix • Cheaper • Made up of rows and columns of conductors. Each pixel is located at the intersection of a row and a column. Current on the grid determines if a pixel is on or off. • Active matrix • One transistor for each pixel. A 1280x800 resolution requires 1024 transistors. • Brighter display • Takes more power
LCD (Liquid Crystal Display) Viewable size is also called VIS or Viewable Image Size
Tech Tips NEVER change the resolution for an LCD monitor, such as on a laptop. Leave it set to the native resolution for optimum output. Most laptop LCDs are expensive to repair, but if it is the inverter that is faulty, it might be cheaper to repair than replace.
Video Adapter with S-video (TV out), DVI, and VGA Ports Figure 9.7
Video Ports • DVI- A port used to connect flat panel monitors to the computer. • Single link – A type of DVI video connection that allows resolutions up to 1920x1080. • Dual link – A type of DVI video connector that allows higher resolution. • DVI-D – A type of video connector used with digital monitors. • DVI-I – The most common type of DVI video connector that is used with both analog and digital monitors.
Video Ports • An upgrade to DVI is HDMI (High-Definition Multimedia Interface), which is a digital interface that can carry audio and video over the same cable. • HDMI is commonly found on cable TV boxes and TVs and is now found on video cards. • Another type of connection you may see on a video card that is not very common is component/RGB video – three RCA jacks labeled YPrPb • Y is for the luminescence or brightness • Pr and Pb are for the color difference signals
Video Ports • To have two monitors connected to a single computer, you have several options: • Use the two video ports on the motherboard (not common). • Use the integrated motherboard port and buy a video card with one video port. • Buy a video card that has two video ports (best option). • Buy two video cards.
Video Ports • Use the same monitor (and sometimes mouse and keyboard) for two different computers • Use a KVM (keyboard, video, mouse) switch, which allows one mouse, one keyboard, and one video output to be used by two or more computers. • Many people would rather use software to do this function and remotely access the desktop of another computer. • Windows calls this feature Remote Desktop.
TV Tuner Card • A TV tuner card allows TV signals to be brought into the computer and output to the monitor. • Some TV tuner cards have the ability to record video.
Video Capture Card • A video capture card usually has specialized software that allows video to be captured from a camera, tape, DVD, recorder, or live audio and video. • The video is then manipulated into a presentation, an archived file, or a saved document or streamed onto the Internet. • Not all video capture cards support audio. • Video surveillance systems sometimes use video capture card. • SLI (Scalable Link Interface) from Nvidia links two or more PCIe video cards to share processing or graphics-intensive operations.
Projectors • A projector allows what is being displayed on the computer to be projected onto a larger screen. • A projector has similar connections as video cards.
Laptops and Projectors Keystrokes For most laptops, you can hold the Fn key and press a specific function key to (1) use only the LCD display; (2) use only the external monitor or projector; or (3) use both the LCD and external video device.
Monitor Preventive Maintenance • Static builds up on the face of the monitorand the screen attracts dust and dirt. • Some monitors also have a button on the front that, when pushed, removes static electricity from the front of the monitor. • Antistatic cleaning wipes are available at computer and office supply stores. • A CRT monitor can also be cleaned with a soft cloth dampened with mild household detergents, glass cleaner, or isopropyl alcohol
LCD Preventive Maintenance • Antistatic cleaning wipes specific for flat panels and laptops are available at computer and office supply stores. • A soft cloth dampened with water or a mixture of water and isopropyl alcohol
Monitor Energy Efficiency • Best practices for monitor energy efficiency • Turn off the monitor with the power switch when you are through for the day. • Use Windows Power Options to enable Sleep mode after a period of inactivity. • On a laptop, adjust the contrast or brightness level to a lower one to prolong the life of the backlight. • If buying a new laptop, consider one that uses an LED backlight instead of CCFL (which has better color accuracy as an added benefit).
Screen Savers • A screen saver changes the image on the monitor constantly to keep any particular image from burning into the screen. • With old monitors, if an image stayed on the screen for an extended period of time, an imprint of the image was left on the screen permanently • Today’s monitors have high enough refresh rates so that screen savers are not necessary • LCDs do not need a screen saver.
Video Adapters • The video adapter controls most of the monitor’s output. Video adapters use the PCI, AGP, or PCI-E interface. The bus connects the video card to the processor. • On the motherboard, the processor and the chipset are responsible for how quickly data travels to and from the video adapter. • Some video adapters have their own processor. • Video processor -Sometimes known as the video coprocessor or video accelerator. • The processor on the video adapter that coordinates communications between the adapter and the system processor.
Video Adapters • Some video processors are 64- or 128-bit processors. • Many users (and technicians) have a hard time understanding how a 128-bit video processor works in a 32-bit or 64-bit expansion slot. • The 64 or 128 bits refers to the number of bits the video adapter’s accelerator chip accepts at one time. • The 64-bit (or higher) video processor controls many video functions on the video adapter otherwise handled by the motherboard processor.
Video Memory • One of the most important functions of the video processor is to transfer data to and from the video adapter’s memory. • Memory chips on the video adapter can be regular DRAM chips (including DDR2 and DDR3).
Video Memory Technologies • VRAM (video RAM) –Dual-ported memory found on video adapters. • RDRAM – Proprietary memory developed by Rambus, Inc. • SGRAM (synchronous DRAM) –Provides very fast burst memory access (approximately 100MHz) by placing new memory addresses on the address but before prior memory address retrieval and execution completes.
Video Memory • This list some video memory technologies: • GDDR3 SDRAM (graphics double data rate SDRAM) Designed by ATI Technologies and is similar to DDR2. Has data rates up to 2Gbps. • GDDR4 SDRAM (graphics double data rate SDRAM) – A power-efficient video memory upgrade to GDDR3 that has speeds up to 3.2GHz.
Video Memory Technologies • GDDR5 – A type of SGRAM that has two parallel sets of data lines with data rates up to 4Gbps or higher. • XDR2 DRAM (extreme data rate 2 DRAM) – Designed by Rambus and based on RDRAM technologies and used in video cards and networking equipment.
Video Memory • The objective is to get data in and out of the video card memory chips as fast as possible for a reasonable cost. • The adapter must handle a large amount of data due to the increasing number of pixels and colors displayed. • Dual-ported memory- A type of memory used on video adapters that allows data to be read from and written to simultaneously.
Video Memory • Memory on the video card stores screen information as a snapshot of what appears on the screen. Common memory chip capacities 128MB, 256MB, 512MB, 768MB, 1GB, and 2GB. • The video adapter manufacturer determines the maximum amount of video memory. • To determine the amount of video memory an adapter needs, multiply the total number of pixels (the resolution) by the number of bits needed to produce a specific number of colors.
