Installing and Configuring Expansion Cards

  • Circuit installed in a computer to increase its capabilities.
  • Drivers needed to make integrated devices function


  • Allows the computer to display some kind of information on monitor
  • Can accelerate the speed of display
  • PCIe is most common slot


  • Sound Card
    • Convert computer signals to sound, integrated now-a-days
    • 1/8” jack to connect ear-phones, speakers, mic
    • Come with a RCA jack
    • Sony/Philips Digital Interface allows audio to transmit in digital quality
  • TV Tuner/Video Capture
    • Connect to broadcast signal like cable television & display output on computer monitor
    • Can be analog, digital or hybrid
    • Video capture card can capture video which can be streamed afterwards


  • Expands system for input or output device like RS232, parallel ports
  • Earlier Super I/O card used
  • SCSI devices requires expanded motherboard capabilities to allow usage
  • Devices cable to adapter which makes the conversions which motherboard can understand


  • Transmit data to other devices
  • Network Adapters (used within administrative domain of home)
    • Connects computer to network
    • Converts parallel data in PC to serial and make frames
    • Can have different connectors like PCI, PCIe, RJ45
    • Wireless NIC: in wired NIC a link is already created but in wireless first the access pints or ad-hoc points must also be configured
  • Cellular Cards: Adapters that can be installed in PC providing cellular service like accessing internet
  • MODEMS (allow direct domestic or international connection via PSTN) most common
    • Connect to internet using a dialup connection
    • Converts digital signals (PC) to analog signals (phone line) and back again
    • Expansion bus for motherboard and other port for phone


  • New Low Profile Extended (NLX), alternate to motherboard form factor
  • Places expansion cards sideways
  • Thus more expansion devices can be accommodated in parallel to motherboard


  • Most are recognized easily by plug and play system
  • Some modern adapters require more special configuration steps
  • Also advanced features need to be implemented using OS or utilities that came with adapters
  • Wired configuration is easier than wireless

Identifying Characteristics of Connectors and Cables



  • Most common with DXn (X=A-E in size, n=no. of pins)
  • Trapezoidal shape with 2 rows of pin
  • D-shape ensures that 1 orientation is possible


  • Used in telecommunications like RJ-11, RJ-45
  • RJ-45 larger and found on Ethernet


  • Universal Serial BUS (USB):
    • Connect upto 127 devices through single port
    • USB .x upto 12MBps
    • USB 2.0 upto 480MBps
    • USB 3.0 upto 5GBps
    • Highly flexible, easy, fast
  • IEEE 1394 (FireWire)
    • Easy, isochronous, very high transmission rates, high power output
    • Not so common
    • Usually used to get digital video into PC
  • Infrared
    • First wireless to exchange data
    • Slow, line of sight communication
  • Audio/Video Jacks
    • RCA jacks transmit audio & video
    • Digital audio implemented by S/PDIF
    • 1/8” jack more common for audio
    • HDMI interface also present
  • PS/2 (Keyboard Mouse)
    • mini-DIN6 connector
    • Keyboard-purple                  Mouse-green
  • Centronics
    • Micro ribbon connector
    • Central bar with outside surrounding ring


Interface is a method of connecting two dissimilar items together



2 types of interfaces

    • Allow FDD and internal tape devices connected to motherboard
    • today these interfaces are nonexistent
    • Serial ATA, EIDE are found on motherboards(40-wire)
    • PATA is very rare. Originally black
    • If blue then ATA5 or above UDMA(80-wire)


Classic Game Port

  • Used to connect joysticks, Musical Instrument Digital Interface(MIDI) devices
  • DA-15F connectors common

Analog Sound Jacks

  • 3.5mm stereo jack
  • for 7.1 surround sound 8 channels required  (7=bandwidth, 1=one low frequency channel)
  • Similar for 3.1, 5.1 surround sound
  • Speakers placed at certain angles to produce the surround sound

Parallel Interfaces

  • Parallel ports faster than original serial
  • Standard Parallel Port
    • Transmits data out of computer at 150KBps
    • Max distance is 10feet
  • Bidirectional Parallel Ports
    • Transmit & receive data
  • Enhanced Parallel Ports
    • IEEE 1284 standard increased the speed
    • Data+address can be sent to memory
    • Virtual extension to main BUS
    • Max distance 15feet
    • Enhanced Parallel Port(EPP) 600KBps-1.5MBps
    • Enhanced Capabilities Port(ECP) accesses DMA
    • DB25 female connector most common
    • 8-wires present


  • Data sent one after another
  • Standard Serial
    • DB-9, DB-25 port
    • 75KBps with maximum length 50feet
    • 2 wiring configurations
      • Standard : hook peripherals like modems, printers
      • Null : No modem required, direct PC to PC
  • USB
    • Most versatile
    • Plug-and-play
    • Drivers easily available or preinstalled
    • 2 types: Type A & Type B
    • USB3.0 SuperSpeed has additional pins for faster data rates
    • USB HUB gives several USB ports from 1 (don’t use more than 5 ports)
    • Hosts not networkable
    • Type A oriented to system from component
    • Type B connect in direction of peripheral component





Shielded from EMI


4 pins

5 extra pins



Supports Bursting


Half Duplex



Wait until polled

Transmitted at will


PC controls power, error

Both ends control power, error


Max 100mA at low & 500mA at high power

Max 150mA at low & 900mA at high power

IEEE 1394(FireWire)

  • High speed and efficiency
  • First iteration FireWire400 rate of 400 MBps
  • Higher power 1.5A at 30VDC than USB
  • Next iteration FireWire800 rate of 800MBps and full duplex over 4.5m with 63 devices connected
  • FireWire400 uses 6-wire cable with 4 for data transmission =>alpha connectors
  • FireWire800 uses 9-wire with beta-connectors
  • Used as universal high-speed data interface for hard disk, optical drives
  • Peripherals can be networked together into WAN, LAN
  • 64000 devices can communicate together without host PC
  • Single device connects to 2 devices and so on, creating daisy-chaining


  • A simple coaxial cable
  • 2 connectors on each side with 2 contacts on each (ground ring, positive in middle)
  • Used to extend audio/video signals


  • Used to connect mouse and keyboard
  • Original AT had 5-pin DIN
  • Once most popular now being replaced by USB


VGA now being replaced with DVI/HDMI as analog by digital

Digital Visual Interface (DVI)

  • Offer high digital standards
  • Similar to D-sub connector but has asymmetrical pins
  •  3 types:
    • DVI-A: Analog only connector. Source and monitor should use analog data
    • DVI-D: Digital only connector. Source and monitor should use digital data
    • DVI-I: Combination of analog/digital. Source and monitor should use analog/digital data
  • DVI-I & DVI-D come in 2 varieties:
    • Single Link
    • Dual Link: has more conductors for higher speed and quality
  • DVI-A, DVI-I are better, faster than VGA
  • DVI-I cannot connect analog to digital
  • Upto 4.5m

High-Definition Multimedia Interface (HDMI)

  • Completely digital dual link but faster frame rate and audio right on same connector
  • Can also support CEC feature that allows transmission from remote device
  • HDMI is compatible with DVI-D DVI-I through proper adapters
  • 3D video sources compatible
  • type B has 19 pins for higher resolution
  • Type C connector for portable devices (mini HDMI)
  • Type D micro HDMI
  • Length can be material dependent from 15-100m

Component Video

  • better-quality video by splitting the red, green, and bluecomponent
  • videoperforms signal-splitting function similar to RGB separation
  • fourth pathway for synchronization
  • To reduce bandwidth:
    • uncompressed signal called luma (Y) represents brightness
    • creates two compressed color-difference signals Pb and Pr. These chrominance (chroma) signals are known as B – Y andR – Y
    • No need for green color-difference signal
    • Capable of transmitting HD video at full 1080p


  • Combines the twochroma signals into one, resulting in video quality not good as YPbPr.
  • 7-pin mini-DIN ports use the extra pins to provide full Y, Pb, and Pr leads with four groundleads, making S-video equivalent to component video
  • 4-pin, 6-pin also available
  • ATI hasused 8-, 9-, and 10-pin versions of the connector that include features as anS-video input path in addition to output, bidirectionalpin, audio input/output.

 Composite Video

  • combines all luma and chroma leads into one
  • Once combined the signals cannot be splitted back
  • A single yellow RCA jack
  • More susceptible to aliasing,cross coloration


  • royalty-free digital display interface from the Video Electronics StandardsAssociation (VESA) that uses less power than other digital interfaces and VGA
  • Functionally similar to HDMI &DVI
  • Can extend 3-33m
  • Thunderbolt combines PCIe with the DisplayPort technology. Less expensive than full-sized DisplayPort. 9-pin IEEE 1394b beta port used.


  • One is terminated by RCA or BNC plugs and serves a single frequency (baseband
  • the other is terminated by F connectors, those seen in cable television (CATV)setting (broadband)


  • Compressed and uncompressed A/V can be sent over IP
  • As with VoIP, quality of service (QoS)must be implemented and supported throughout the data network or A/Vquality will surely suffer

Input Devices

 Transfers information from outside to internal storage memory


  • hand-fitting device uses motion-detection mechanism
  • translate physical two-dimensional movement into onscreen cursor motion
  • balls, tablets, touchpads, and pointing sticks
  • Ball based motion detection initially, now lasers
  • Wired or wireless
  • 1 or 2 or more buttons plus a wheel for scrolling
  • Touch pads—flat panels below the spacebar—and pointing sticks—eraser-like protrusionsin the middle of the keyboard—are found mainly on laptops
  • trackballis morelike an inverted mouse, so let’s look at how they compare to each other


  • standard QWERTY layout, now have separatecursor-movement and numerical keypads
  • Function keys also included
  • keys complete individual circuits when pressed sending unique scan code
  • controller decodes the code and tells PC which key is pressed


  • Before USB connected with SCSI bus
  • Hand held scanners included software to intelligently stitch together the scanned ribbons into image
  • Emit light and measure the reflected light to detect image
  • Charge coupled devices (CCDs)convert light into electrical impulses producing image
  • combination of scanner copier printer fax is very popular


  • Input device used in retail& industrial sectors that manage inventory
  • Use LED/laser to scan 2D barcodes
  • USB most common
  • Thescanner converts output to keyboard scans so that the system treats the input as keyboard
  • Universal ProductCode (UPC) barcodes and Quick Response (QR) codes and other 2D matrix barcodes can beinput and processed using smart phone cameras


  • Trace an analog source, turning it into a digital representation
  • Act of turning any analog source—artwork,audio, video, slides and photographs—into a binary bit stream


  • Measures physical or behavioral features of an organism
  • Fingerprint scanners, retinal and iris scanners, voice recognition devices
  • A computer can use this input to authenticatethe user


  • Converts touching of screen to electric impulses
  • Replace mouse in movement and click
  • Technology also seen in PDAs, smartphones, ATMs
  • Resistive and capacitive most popular technologies
  • Generally USB interfaced


  • Allows to switch b/w input devices
  • mouse/keyboard to mini-DIN, monitor to VGA/HDMI
  • Use same I/P to multiple PCs


  • Specialty controllers for games
  • Joystick: analog buttons with variable bar
  • Gamepad: function and direction buttons
  • DB25/DE9/DA15/USB ports


  • Webcams
    • Video-camera device for capturing videos
    • Used for security, video conferencing
    • USB/WiFi
  • MIDI Devices
    • Microphones, audio playback as audio input
    • MIDI controller creates messages synthesizing user’s music
    • MIDI files are small files containing digitalized audio waveforms
    • 5-pin DIN connectors
    • Direct connection or daisy chaining but it produces delays
  • Digital Cameras & Camcorders
    • Digital camera takes still pictures
    • camcorder takes videos
    • Now devices do both
    • Have inbuilt batteries and flash memory for easy storage
    • Mostly transferred via USB



  • To produce hardcopy of data
  • Impact, inkjet, laser
  • Parallel, serial, USB


  • Speakers and orientations have already been discussed


  • configuration is Plug and Play
  • Easy to install
  • Rest will be discussed in next chapter

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Practice Test

 Computer Hardware Technician Interview Questions

Sample Resume