FRAM® high performance - oil filter adapter kit

 Interface between computer and a display device  Unless a computer has graphics capability built into the motherboard, the video card is required..  With high-performance standards l

Video Cards

CS431 Class Presentation

Ashish Bhat (02007025)

Nilesh Meshram (02007027)

 Interface between computer and a display device

 Unless a computer has graphics capability built into the motherboard, the video card is required

 The CPU, working in conjunction with software

applications, sends information about the image to the video card The video card decides how to use the pixels on the screen to create the image It

then sends that information to the monitor through output interface

The Evolution of Video Cards

 IBM introduced the first video card in 1981 called a Monochrome Display Adapter (MDA), which

provided text-only displays of green or white text

on a black screen

 Presently, the minimum standard for new video

cards is Video Graphics Array (VGA), which allows

256 colors

 With high-performance standards like Quantum

Extended Graphics Array (QXGA), video cards can display millions of colors at resolutions of up to

2040 x 1536 pixels

Components in a Video Card

 Graphics Controller / Graphic Processing

Unit (GPU)

 Digital-to-analog Converter (DAC)

 Attribute Controller

 Output Interface - RGB, Composite, DVI

 BUS Interface

 BIOS

Components in a Video Card

Video Card - GPU

 Similar to CPU but designed specifically to perform complex mathematical and

geometric calculations necessary for

graphics rendering

 Less congestion on the system bus

 Reduction in the workload of CPU

Video Card - GPU

 Operations: bitmap transfers, painting,

window resizing and repositioning, line

drawing, font scaling and polygon drawing etc.

algorithms built-in

– e.g 3D edge smoothening

Video Card - GPU

 Some of the latest

GPUs have more

transistors than

average CPU and

produce a lot of heat

Heat-sinking and fan

cooling are required

Video Card - Memory

 Video Memory (RAM) is used for:

– Frame Buffering: holding completed imaged until

its time to display them

– As the GPU creates images, the image

information is stored in this video memory frame buffer as a digital bitmap

– Total amount of video memory installed may not

be needed for a particular resolution, the extra memory often used for caching information for the graphics processor

for example, the caching of commonly used

graphical items, such as text fonts and icons

 Unified memory architecture: Use of portion of

system memory as frame buffer

- Cost reduction

- Inferior graphics performance

 The greater number of colors, or higher the

resolution, the more video memory will be required

 However, since it is a shared resource reducing one will allow an increase in the other

Video Card - Memory

Video Card - DAC

 RAM connects directly to DAC

– known as RAMDAC

 Used to convert the digital image information stored

in video memory into analog signals that a monitor can use

 The range of refresh rates decided by:

- The rate at which the RAMDAC converts the

information

- The design of the graphics processor

 Multiple RAMDAC

 Resolution

- specified in terms of a row by column figure

- the maximum number of displayable pixels

- determined by the beam size and dot pitch

- refers to the sharpness, or detail of the visual image

 Color Depth

determined by the intensity of three beams of light (Red, Green and Blue) and the amount of information stored about a pixel

 Different Modes

8 Bit – 256 Color Mode

16 Bit – High Color mode

24 Bit – True Color Mode

Video Cards - Resolution and

Color depth

Video Card - Attribute Controller

 Contains the Color Look-up-table

(CLUT) which determines which

color will be displayed for a

given pixel value in the video

memory

 Used when the display mode is

not true color (24bit or 48bit)

In such cases the most used

colors are stored in this CLUT

 Dithering

- uses two colors to create the

appearance of a third

- gives a smoother appearance

to abrupt transitions example color palette

Video Cards – Resolution

and Colors

16.7 million 1600x1200

Ultra XGA UXGA

16.7 million 1280x1024

Graphics Array SXGA

16.7 million 1024x768

Extended Graphics Array XGA

1990

16 from 262,144 256

640x480 320x200

Video Graphics Array

VGA

1987

16 from 64 640x350

Enhanced Graphics Adapter

EGA

1984

None 16

640x200 160x200

Color Graphics Adapter

CGA

1981

No of colors Resolution

Description Standard

Da

te

 CRT controller in the video card generates horizontal and vertical sync signals

Output Interface - Composite

 Composite video interface is used in

Television

 First RGB data is converted into

chrominance (color) and luminescence

(intensity) signals and then both are time

multiplexed with horizontal and vertical sync signals to give a single composite video

signal

Output Interface - DVI

 LCD Monitors work in

digital mode and require

display data in digital

form

 RAMDAC is thus

bypassed and data is

sent directly in digital

form This interface is

known as DVI (Digital

Video Interface) Output interface requirement for different monitors

Video Card - BUS Interface

 ISA Interface (Obsolete)

 PCI Interface (Obsolete)

 AGP Interface

 PCI Express Interface

AGP Interface

 AGP = Accelerated Graphics Port

 Single dedicated Point-to-point Connect

 Pipelined transfers

 Video RAM Sharing

 Being replaced by new PCI Express

Video Card - BIOS

 Initialization of hardware setting during

boot-up

 Provides a set of standard routines to

control and use the video card

– e.g change display mode, gotoxy,

change color, write text etc.

– traditionally video cards were built according to

certain standards (CGA, VGA, SVGA etc.) and provided the same functionality through these standard routines

Video Card Interfacing

 Older video cards provide a set of standard routines accessed through BIOS

 Display Drivers

Video Card Interfacing in Windows

 http://www.howstuffworks.com

 http://www.pctechguide.com/

 http://www.epanorama.net

Thank you!

Video Card – Types of

Memory

 Standard DRAM – Used in earlier system

 Video memory implementation on graphics board