Video Card Concepts & Troubleshooting

Video Card Concepts

• Acts as a hardware interface between monitor and PC


• Has its own chipset and RAM, like a motherboard


• Talks to the OS via a driver

Video Card Concepts

Video Card Concepts

Video Resolution

• Pixels: Individual dots in a particular display resolution
  
• Examples:
  640x480
  800x600
  1024x768

Monitor Resolution

• Triad: One set of one red, one green, one blue phosphor


• Number of triads per pixel depends on display resolution chosen in OS
  
  

Video Card Types

• PCI Express:
  *New type of motherboard slot in 2004
  *Faster than AGP


• AGP:
  *AGP slot on motherboard designed specifically for video card
  *Fast interface
  

Video Card Types

Video Chipset

• Not always the same brand as the video card itself


• Determines overall driver class compatibility

Video RAM

• How Much RAM needed for a particular resolution?
  *Horizontal resolution x vertical resolution x color depth in bits
  *Convert answer to bytes by dividing by 8
  *Example: 1024 x 768, 24-bit color
  *Number of pixels: 1024 x 768 = 786,432
  *Bits required: 786,432 x 24 = 18,874,368
  *Convert to bytes: 18,874,368 ÷ 8 = 2,359,296

3D Acceleration

• Increases amount of RAM required by about 4X because extra RAM is needed for buffers
  

Install a Video Card

1.Remove old video card if needed
2.Remove backplate from slot if needed
3.Insert video card firmly in slot
4.Secure it with screw or retainer bar
5.Connect a monitor, and boot

Set Display Properties in Windows

1.Install correct driver for video card if needed
2.Right-click the desktop, choose Properties
3.Change resolution and color depth on Settings tab

Troubleshooting Video Card

• Nothing appears on-screen
  *Monitor turned off
  *Monitor contrast turned down
  *Monitor not connected
  *PC not powered on
  *Defective video card
  *Not installed correctly
• Screen has a red, blue, or green tint
  *Pin broken on monitor or video card connector
  *Connector not snugly plugged in
• Garbled Windows display
  *Bad video driver
  *Correct problem in Safe Mode
• Vertical stripes on Windows display
  *Corrupted video driver
  *Physical defect in video card
  *Not the monitor’s fault
• Windows won’t start except in safe mode
  *Bad Windows video driver
  *Wrong driver installed for video card
• Pictures and colors look bad
  *Too low a color depth being used
  *Video card not recognized, so it is using standard VGA mode (16 color)
  *Install driver for exact model of video card
• Certain Applications Crash
  *Video driver not up-to-date
  *Patch for application required
  *New version of DirectX required