Display adapters

Introduction Display adapter is a circuit board. This is used to convert the raw data to image data (video signal) that can be displayed on the monitor.

Convert the raw data to image Raw Data Display Adapter card Display Adapter card Image Data

Display adapters The following are the important display adapters VGA SVGA

VGA This display adapter was introduced in 1987 by IBM.

Features of VGA It offers 640 x 480, flers 640 x 360, and 320 x 200 pixels in 16 colors and 320 x 200 in 256 colors It has a selectable MHz or MHz master clock It has a 256 KB of video RAM It produces high quality text and graphics in 64 colors from a palette of 256 colors Its refresh rate is 70Hz

Cont., It supports split screen. That is, a display technique used to divide the graphics and text into two or four rectangular area It supports smooth scrolling of text or images across the display.

VGA Pin connection

SVGA This display adapter was introduced in 1989 standard association by video electronics

Features of SVGA It offers very high resolution of 800 x 600 and 1024 x 768 pixels in 16 colors It supports both graphics and text mode It has 0.5 MB or 1 MB video buffer RAM It offers 32 bit interface It offers wide range of colors (256 colors) It supports VESA BIOS extensions It supports multimedia It supports Microsoft Windows that allows more icons and folders on the screen without having to scroll.

Pin connection of SVGA

Flickering Flickering is nothing but unsteadiness present in the display area of the monitor. When we view the flickering monitor for long period, it causes more eye strain Flickering is caused by low refresh rate setting for the monitor. Normally windows by default set our monitor refresh rate by 60Hz. This may not be sufficient and this leads to flickering.

Flickering of a Monitor

Change the refresh rate in Windows XP Right click an empty area on the desktop and select Properties. Display properties dialog box appears

Cont., Select setting tab

Cont., Click the Advanced button. Plug and Play monitor dialog box appear.

Cont., Click on the monitor tab

Cont., From the screen refresh rate select 75 or 85 Hz Click Apply. The setting will be saved

Demagnetizing A monitor gets magnetized because of the following reasons When the monitor is moved or just rotated When there is a lightning strike nearby When a permanent magnet is brought near the screen When a piece of electrical or electronic equipment without cover is brought near the monitor

Demagnetize of a monitor

Cont., Magnetizing causes color problems in the display. Therefore we have to demagnetize the monitor for clarity. By following the steps given bellow we can demagnetize the monitor. Most modern monitors demagnetize automatically when it is turned on every time. This can be confirmed by a doing sound every time monitor switched on. If we didn’t hear this sound, the monitor may not demagnetize automatically.

Cont., If not demagnetize automatically, open the on-screen menu using the button present in front of the monitor. Locate the degause option and select it. Now the monitor gets demagnetized

Precautions of Demagnetize Use demagnetizing whenever needed. If used oftenly the degaussing coil may get and burnt off.

Cont., Don’t try to demagnetize by opening the back overheated and burnt off Don’t try to demagnetize with the help of permanent magnet. Sometime it may cause more problems.

The End ….. Thank you….