Graphics CardsGraphics Cards

Presentation by David FongPresentation by David Fong

What are graphics cards What are graphics cards used for?used for?

AnimationAnimation Gaming – both PC and consoleGaming – both PC and console Design/DraftingDesign/Drafting Special effects creation/editingSpecial effects creation/editing Medical InstrumentsMedical Instruments And other purposes where fast And other purposes where fast

rendering and high resolutions are rendering and high resolutions are neededneeded

HistoryHistory

Over the years, more colors, higher resolution, faster bus Over the years, more colors, higher resolution, faster bus interfaces, and more memory.interfaces, and more memory.

HistoryHistory

Monochrome Display Adapter (MDA) Monochrome Display Adapter (MDA) was the first video card created in 1981 was the first video card created in 1981 – displays green text on black screen– displays green text on black screen

Video Graphics Array (VGA) = very Video Graphics Array (VGA) = very popular and was the standard in almost popular and was the standard in almost every PC up until recentlyevery PC up until recently

First 3d video cards were released in First 3d video cards were released in 1995 and they used SVGA; learned to 1995 and they used SVGA; learned to create 3d effectscreate 3d effects

Monochrome MonitorMonochrome Monitor

ComponentsComponents

Graphics Processing Unit (GPU): perform Graphics Processing Unit (GPU): perform calculations for rendering and figure out calculations for rendering and figure out what to do with each pixelwhat to do with each pixel

Video Memory: storing images and Video Memory: storing images and information about each pixelinformation about each pixel

Output: Common outputs include Video Output: Common outputs include Video Graphics Array (VGA) for CRT monitors, Graphics Array (VGA) for CRT monitors, Digital Visual Interface (DVI) for flat panel Digital Visual Interface (DVI) for flat panel displays, and Video-in-video-out (ViVo) for displays, and Video-in-video-out (ViVo) for television and video camerastelevision and video cameras

ComponentsComponents Heat sink and Fan: used to cool the GPU, Heat sink and Fan: used to cool the GPU,

just like the CPU of a computer having the just like the CPU of a computer having the same cooling instrumentssame cooling instruments

Motherboards: PCI before AGPMotherboards: PCI before AGP Motherboards: Accelerated Graphics Port Motherboards: Accelerated Graphics Port

(AGP) compatible popular decade ago; (AGP) compatible popular decade ago; Peripheral Component Interconnect Peripheral Component Interconnect Express (PCI-E) gaining popularityExpress (PCI-E) gaining popularity

BIOS chip that stores settings, information BIOS chip that stores settings, information about each component of the graphics about each component of the graphics cards, and can be altered for over-clockingcards, and can be altered for over-clocking

Picture of Graphics CardPicture of Graphics Card

How graphics cards How graphics cards work?work?

Take data from CPU and figure out what Take data from CPU and figure out what to do with each pixel to create imageto do with each pixel to create image

Create wire frame using vectorsCreate wire frame using vectors Fill remaining pixels with color, lighting, Fill remaining pixels with color, lighting,

and textureand texture The filling will consider viewpointThe filling will consider viewpoint For games and video, the graphics cards For games and video, the graphics cards

has to do the above steps for 30 frames has to do the above steps for 30 frames per secondper second

How graphics cards How graphics cards work?work?

In greater detail:In greater detail: GPU creates image, stores image with GPU creates image, stores image with

location and color of each pixel in memorylocation and color of each pixel in memory Memory also holds completed images until Memory also holds completed images until

it’s time to display them (frame buffer)it’s time to display them (frame buffer) Digital-to-analog converter (DAC) is Digital-to-analog converter (DAC) is

connected to memory and translates connected to memory and translates image into analog signals that is sent image into analog signals that is sent through monitor cable and the image is through monitor cable and the image is displayed on monitordisplayed on monitor

Wire imageWire image

Draw 12 lines for cube, then fill inDraw 12 lines for cube, then fill in A curve is created by many short A curve is created by many short

lineslines

3d Image Development3d Image Development

3d effect: Mip-Mapping3d effect: Mip-Mapping

Pre-calculated images of target Pre-calculated images of target imageimage

Target image, may have several Target image, may have several copies which is ¼ the size of copies which is ¼ the size of previous imageprevious image

Makes rendering faster when the Makes rendering faster when the output is moving toward and further output is moving toward and further away from a target imageaway from a target image

3d effect: Z-buffering3d effect: Z-buffering

Each pixel is part of a 2d coordinate Each pixel is part of a 2d coordinate (x-y coordinates)(x-y coordinates)

Depth is z-coordinateDepth is z-coordinate When a new object that is rendered When a new object that is rendered

wants to take a pixel, Z-buffering wants to take a pixel, Z-buffering checks which pixel is closer to the checks which pixel is closer to the observer, the old pixel or the new observer, the old pixel or the new pixel based on the z-coordinatepixel based on the z-coordinate

If new pixel is closer, the new pixel is If new pixel is closer, the new pixel is buffered and replaces old pixelbuffered and replaces old pixel

3d effect: Anti-aliasing3d effect: Anti-aliasing

When trying to represent high When trying to represent high resolutions signal at lower resolutions signal at lower resolutions.resolutions.

Smoothes out edges to the human Smoothes out edges to the human eye by blending of colorseye by blending of colors

Anti-aliasingAnti-aliasing

Anti-aliasingAnti-aliasing

Anti-aliasingAnti-aliasing

Anti-AliasingAnti-Aliasing

Anti-AliasingAnti-Aliasing

Extra FeaturesExtra Features

ATI and nVidia added enhancements ATI and nVidia added enhancements to their GPUs including:to their GPUs including: Anti-aliasing which makes smoother Anti-aliasing which makes smoother

edges for 3d objectsedges for 3d objects Anisotropic filtering: creating crisper Anisotropic filtering: creating crisper

imagesimages Dual-monitor support which can Dual-monitor support which can

increase productivityincrease productivity TV-tunerTV-tuner

Do you need a graphics Do you need a graphics card?card?

If you only surf the web, watch If you only surf the web, watch streaming videos, chat, or word streaming videos, chat, or word processing, the integrated graphics processing, the integrated graphics processor on your motherboard is processor on your motherboard is enough.enough.

If you play games or work with 3d If you play games or work with 3d graphics, then a graphics card is graphics, then a graphics card is recommended.recommended.

How to judge quality of How to judge quality of graphics card?graphics card?

Most of the time, you can judge the quality Most of the time, you can judge the quality of a graphics card by the processor speed of a graphics card by the processor speed and how much memory the card has.and how much memory the card has.

There are some sites that do benchmark There are some sites that do benchmark tests (www.tomshardware.com) for tests (www.tomshardware.com) for comparable cards by running graphics comparable cards by running graphics intensive games or environments and intensive games or environments and measuring the frame rate (frames per measuring the frame rate (frames per second)second)

Higher the frames per second, the smoother Higher the frames per second, the smoother the transitions for frames in games and videothe transitions for frames in games and video

ManufacturersManufacturers Intel: develop IGPs (integrated graphics Intel: develop IGPs (integrated graphics

processors)processors) AMD (acquired ATI) develop GPUsAMD (acquired ATI) develop GPUs Nvidia also develop GPUsNvidia also develop GPUs Different manufacturers take GPUs and other Different manufacturers take GPUs and other

components to assemble video cards; thus components to assemble video cards; thus creating slight variations of video cards with creating slight variations of video cards with same GPUssame GPUs

Video cards are marketed with GPU Video cards are marketed with GPU manufacturer’s brand namemanufacturer’s brand name

Most popular video brands are the Radeon of Most popular video brands are the Radeon of ATI and GeForce of NvidiaATI and GeForce of Nvidia

IGPs vs Graphic CardsIGPs vs Graphic Cards

About 90% of computers use IGPsAbout 90% of computers use IGPs IGPs use the memory in the system instead IGPs use the memory in the system instead

of having dedicated video memory like of having dedicated video memory like Graphics CardsGraphics Cards

IGPs are way cheaper than Graphics CardsIGPs are way cheaper than Graphics Cards Performance always favors Graphics CardsPerformance always favors Graphics Cards Almost impossible to play high end games Almost impossible to play high end games

on IGPson IGPs

How much video memory How much video memory you need?you need?

Depends on resolution and bits per pixel Depends on resolution and bits per pixel (how many colors possible for pixel)(how many colors possible for pixel)

32bpp = 2^32 = 4,294,967,296 colors32bpp = 2^32 = 4,294,967,296 colors Minimum memory = Resolution x bppMinimum memory = Resolution x bpp Example: 1024 x 768 x 32 bits per pixelExample: 1024 x 768 x 32 bits per pixel

25,165,824 bits / (8 bits per byte)25,165,824 bits / (8 bits per byte) 3,145,728 bytes3,145,728 bytes So need a little bit more than 3 MB of So need a little bit more than 3 MB of

memorymemory

FutureFuture Because of growing processor speeds, there Because of growing processor speeds, there

may be a need to develop a faster way for the may be a need to develop a faster way for the CPU to transfer bits to the GPU (like how CPU to transfer bits to the GPU (like how AGP was needed a decade ago, and PCI-E few AGP was needed a decade ago, and PCI-E few years ago)years ago)

With greater GPU speeds, comes greater With greater GPU speeds, comes greater demand for power (a simple PCI-E connection demand for power (a simple PCI-E connection is not enough to power a high quality is not enough to power a high quality graphics cards these days, most likely needs graphics cards these days, most likely needs additional sockets to be connected for power)additional sockets to be connected for power)

The growth in processor speed and memory The growth in processor speed and memory will create higher fps at greater resolutions will create higher fps at greater resolutions

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How to calculate the minimum How to calculate the minimum amount of video memory you need?amount of video memory you need?

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What was the most popular bus What was the most popular bus interface before PCI-E?interface before PCI-E?

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How do most benchmark tests How do most benchmark tests measure the performance of a measure the performance of a graphics card?graphics card?

SourcesSources

Howstuffworks.comHowstuffworks.com Wikipedia.orgWikipedia.org Encarta.msn.comEncarta.msn.com Brighthub.comBrighthub.com Pcwize.comPcwize.com