COMP 364 Jess Role @ UEAB 2006 AGP Video Cards. COMP 364 Jess Role @ UEAB 2006 What is a Graphics Card? A video card or graphics card is the name we give

COMP 364 Jess Role @ UEAB 2006COMP 364 Jess Role @ UEAB 2006

AGP Video CardsAGP Video Cards


What is a Graphics Card?What is a Graphics Card?A video card or graphics card is the name we give to the A video card or graphics card is the name we give to the

piece of hardware responsible for converting binary piece of hardware responsible for converting binary representation of computer graphics into a video signal representation of computer graphics into a video signal

for an output device (e.g. monitor, projector, etc)for an output device (e.g. monitor, projector, etc)

Integrated on the motherboard or as a removable card.


A (very) Brief History of the A (very) Brief History of the Graphics Card on the IBM-Graphics Card on the IBM-

compatible PCcompatible PC1981 -- Monochrome Display Adapter (MDA)

1981 – Color Graphics Adapter (CGA)

Could display up to 16 colors, but at the most common resolution, only 4 colors could be accessed.

Could only display green-on-black text. Could not address individual pixels on screen.



compatible PCcompatible PC1984 – Enhanced Graphics Adapter (EGA)

1987 – Video Graphics Array (VGA)

Full 16 color palette support.

The last “well defined” graphics standard.

IBM wasn’t the only manufacturer of video hardware.



compatible PCcompatible PC1989 - Present -- Super VGA

NOT a standard. A “catch all” phrase used to describe post-VGA graphics cards.

IBM no longer defines the graphics standards.

1996 – Advent of 3d Acceleration

1997 – The “modern” video card

Combined 2d and 3d support on ONE card instead of two.


AGP vs. PCI-EAGP vs. PCI-EAccelerated Graphics Port Accelerated Graphics Port (AGP) requires a chipset with (AGP) requires a chipset with a graphics address relocation a graphics address relocation table (GART) , which provides table (GART) , which provides a linear view of nonlinear a linear view of nonlinear system memory to the system memory to the

graphics device.graphics device.

Peripheral Component Peripheral Component

InterconnectInterconnect (PCI-E) requires (PCI-E) requires that the memory linearization that the memory linearization hardware exist on the graphics hardware exist on the graphics device itself instead of on the device itself instead of on the chipset chipset

AGP graphics card PCI-E


Overview of how a graphics card Overview of how a graphics card works. works.

AGPAGP– Has a dedicated AGP Has a dedicated AGP

chipset to connect to chipset to connect to the Frontside bus, the Frontside bus, which directly which directly connects to the CPUconnects to the CPU

PCI/PCI-ePCI/PCI-e– Connects to the PCI-Connects to the PCI-

bus, which connects bus, which connects to the Bus Bridgeto the Bus Bridge

– BusBridge acts as a BusBridge acts as a traffic light for all traffic light for all incoming and incoming and outgoing signals from outgoing signals from all PCI devices to the all PCI devices to the CPUCPU


Overview of how a graphics card Overview of how a graphics card works (con’t)works (con’t)

Texture mapping:Texture mapping:– Any 3-D graphic you see on your computer is built by a texture Any 3-D graphic you see on your computer is built by a texture

map. map. – Texture maps are like wrapping paper. Your computer takes a Texture maps are like wrapping paper. Your computer takes a

flat, 2-D image and wraps it around a set of parameters dictated flat, 2-D image and wraps it around a set of parameters dictated by the graphics card to create the appearance of a 3-D image. by the graphics card to create the appearance of a 3-D image.

– Drains the memory overall.Drains the memory overall.


AGPAGPAGP built using PCI’s framewok (PCI wasted AGP built using PCI’s framewok (PCI wasted memory by storing texture maps twice)memory by storing texture maps twice)

AGP improves storage - allowing OS to AGP improves storage - allowing OS to designate RAM.designate RAM.

This type of memory is called This type of memory is called AGP memoryAGP memory or non-local video memory. or non-local video memory.

Using RAM for texture maps (sharing between Using RAM for texture maps (sharing between AGP memory and RAM).AGP memory and RAM).

Storage limit not affected by the amount of Storage limit not affected by the amount of RAM on the graphics card.RAM on the graphics card.

Graphics Address Remapping Table Graphics Address Remapping Table (GART). (GART). – GART takes the portion of the system memory and re-GART takes the portion of the system memory and re-

addresses it. addresses it. – The new address provided by GART makes the CPU think The new address provided by GART makes the CPU think

that the texture map is being stored in the cards that the texture map is being stored in the cards framebuffer. framebuffer.

– GART may be putting bits and pieces of the map all over GART may be putting bits and pieces of the map all over the system RAM; … as far as the cpu is concerned the the system RAM; … as far as the cpu is concerned the texture map is right where it should be.texture map is right where it should be.

Photo courtesy Intel CorporationPhoto courtesy Intel CorporationDiagram of the standard architecture of a Diagram of the standard architecture of a Pentium III-based system using AGPPentium III-based system using AGP


PCI Express (PCIe)PCI Express (PCIe)PCI ExpressPCI Express is a serial is a serial connection that operates more like connection that operates more like a network than a a network than a busbus. . – Instead of one bus that handles Instead of one bus that handles

data from multiple sources, PCIe data from multiple sources, PCIe has a switch that controls several has a switch that controls several point-to-point serial connections. point-to-point serial connections.

– These connections fan out from These connections fan out from the switch, leading directly to the the switch, leading directly to the devices where the data needs to devices where the data needs to go. go.

– Every device has its own Every device has its own dedicated connection, so devices dedicated connection, so devices no longer share bandwidth like no longer share bandwidth like they do on a normal bus. they do on a normal bus.

Devices using PCI share a common bus, but Devices using PCI share a common bus, but each device using PCI Express has its own each device using PCI Express has its own dedicated connection to the switch.dedicated connection to the switch.


Characteristic for both AGP and PCI-E Characteristic for both AGP and PCI-E

Resolution - a term often used interchangeably with addressability, but it more properly refers to the sharpness, or Resolution - a term often used interchangeably with addressability, but it more properly refers to the sharpness, or detail, of the visual image. detail, of the visual image.

Color Depth - Each pixel of a screen image is displayed using a combination of three different color signals: red, Color Depth - Each pixel of a screen image is displayed using a combination of three different color signals: red, green, and blue. The more bits that are used per pixel, the finer the color detail of the image. green, and blue. The more bits that are used per pixel, the finer the color detail of the image.

Video memory – The memory that holds the video image is also referred to as the frame buffer and is usually Video memory – The memory that holds the video image is also referred to as the frame buffer and is usually implements on the graphics card itself.implements on the graphics card itself.

– Video RAM (VRAM) : a special type of dual-ported DRAM, which can be written to and read from at the Video RAM (VRAM) : a special type of dual-ported DRAM, which can be written to and read from at the same time. It also requires far less frequent refreshing than ordinary DRAM and consequently performs same time. It also requires far less frequent refreshing than ordinary DRAM and consequently performs much better much better

– Windows RAM (WRAM): as used by the hugely successful Matrox Millennium card, is also dual-ported and Windows RAM (WRAM): as used by the hugely successful Matrox Millennium card, is also dual-ported and can run slightly faster than conventional VRAM can run slightly faster than conventional VRAM

– EDO DRAM: which provides a higher bandwidth than DRAM, can be clocked higher than normal DRAM and EDO DRAM: which provides a higher bandwidth than DRAM, can be clocked higher than normal DRAM and manages the read/write cycles more efficiently manages the read/write cycles more efficiently

– SDRAM: Similar to EDO RAM except the memory and graphics chips run on a common clock used to latch SDRAM: Similar to EDO RAM except the memory and graphics chips run on a common clock used to latch data, allowing SDRAM to run faster than regular EDO RAM data, allowing SDRAM to run faster than regular EDO RAM

– SGRAM: Same as SDRAM but also supports block writes and write-per-bit, which yield better performance SGRAM: Same as SDRAM but also supports block writes and write-per-bit, which yield better performance on graphics chips that support these enhanced features on graphics chips that support these enhanced features

– DRDRAM : Direct RDRAM is a totally new, general-purpose memory architecture which promises a 20-fold DRDRAM : Direct RDRAM is a totally new, general-purpose memory architecture which promises a 20-fold performance improvement over conventional DRAM. performance improvement over conventional DRAM.

Bandwidth - the rate at which data can flow through it, and is measured in MB/sec. Basically, as graphic Bandwidth - the rate at which data can flow through it, and is measured in MB/sec. Basically, as graphic performance increases, so does the amount of video memory and bandwidth you need. Memory Bandwidth = performance increases, so does the amount of video memory and bandwidth you need. Memory Bandwidth = speed of the memory * width. speed of the memory * width.


Two Major Graphics Cards Two Major Graphics Cards companiescompanies

ATI TechnologiesATI Technologies – a Canadian major supplier of graphics a Canadian major supplier of graphics

cards, graphics chips and graphics cards, graphics chips and graphics processing units for personal processing units for personal computers computers

– developed a dual-GPU system based developed a dual-GPU system based on PCIe called Crossfire.on PCIe called Crossfire.

nVIDIAnVIDIA– is a major supplier of graphics is a major supplier of graphics

processors (graphics processing units, processors (graphics processing units, GPUs), graphics cards, and media and GPUs), graphics cards, and media and communications devices for PCs and communications devices for PCs and game consoles such as the original game consoles such as the original XBOX and the new upcoming 'next XBOX and the new upcoming 'next generation' Playstation 3generation' Playstation 3

– Uses the high-speed data transfer of Uses the high-speed data transfer of PCIe for its newly developed Scalable PCIe for its newly developed Scalable Link Interface (SLI) technology, which Link Interface (SLI) technology, which allows two graphics cards of the allows two graphics cards of the exactexact same chipset and model number to be same chipset and model number to be run at the same time, allowing run at the same time, allowing increased peroformance.increased peroformance.


nVidia SLInVidia SLI

NVIDIA Scalable Link Interface (SLI)NVIDIA Scalable Link Interface (SLI) With an SLI-certified motherboard, two SLI With an SLI-certified motherboard, two SLI graphics cards and an SLI connector, a user graphics cards and an SLI connector, a user can put two video cards into the same can put two video cards into the same system. system.

How it works:How it works:

– The cards work together by splitting The cards work together by splitting the screen in half. the screen in half.

– Each card controls half of the screen, Each card controls half of the screen, and the connector makes sure that and the connector makes sure that everything stays synchronized.everything stays synchronized.


ATI CrossFireATI CrossFire

ATI CrossFireATI CrossFire: : Two ATI Radeon® video cards, Two ATI Radeon® video cards, one with a "compositing engine" one with a "compositing engine" chip, plug into a compatible chip, plug into a compatible motherboard. ATI's technology motherboard. ATI's technology focuses on image quality and does focuses on image quality and does not require identical video cards, not require identical video cards, although high-performance although high-performance systems must have identical systems must have identical cards. cards.

Three rendering modes: Three rendering modes: – Scissoring Scissoring – CheckerboardCheckerboard– Odd/even frames Odd/even frames


Other companiesOther companies

PNYPNY

Sapphire Sapphire

XFXXFX

EVGAEVGA

ASUSASUS


Consequences of the different Consequences of the different types of video cardstypes of video cards


Performance – AGP vs PCI-EPerformance – AGP vs PCI-E

BandwidthBandwidth - AGP 8X (2,100 MB/s) - AGP 8X (2,100 MB/s) - PCI-E 16X (4000 MB/s). - PCI-E 16X (4000 MB/s).

GPUGPU Fastest nVidia AGP card: GeForce 7800GSFastest nVidia AGP card: GeForce 7800GS 3dMark06: 16213dMark06: 1621 Fastest nVidia PCI-E card: 7900GTXFastest nVidia PCI-E card: 7900GTX 3dMark06: 47823dMark06: 4782 Fastest ATI PCI-E card: Radeon X1900 XTXFastest ATI PCI-E card: Radeon X1900 XTX 3dMark06: 49033dMark06: 4903 Fastest ATI AGP card:X850XT PEFastest ATI AGP card:X850XT PE 3dMark06:13923dMark06:1392**scores collected from tomshardware.comscores collected from tomshardware.com


OutputOutput

Whether it is PCI-E or AGP another consequence between video cards are the Whether it is PCI-E or AGP another consequence between video cards are the options you have of outputting display to your monitor. The most common options are options you have of outputting display to your monitor. The most common options are analog, DVI and S-Video. The difference between these is that DVI offers better analog, DVI and S-Video. The difference between these is that DVI offers better image quality compared to analog, while S-Video is more commonly used for image quality compared to analog, while S-Video is more commonly used for outputting to a TV. Although the difference doesn’t matter to the average user, it outputting to a TV. Although the difference doesn’t matter to the average user, it would to someone who needs precise image quality. DVI output can be found on would to someone who needs precise image quality. DVI output can be found on most LCD monitors and few CRT monitors. If you have on-board then most likely most LCD monitors and few CRT monitors. If you have on-board then most likely there is just a single analog output.there is just a single analog output.


GPU – ATI vs nVidiaGPU – ATI vs nVidia

The last consequence with the differences between cards is The last consequence with the differences between cards is the difference between GPUs on the card. The two major the difference between GPUs on the card. The two major manufacturers are of course ATI and nVidia. While the manufacturers are of course ATI and nVidia. While the performance between the two is relatively the same, it’s more performance between the two is relatively the same, it’s more of personal preference which one to decide on of personal preference which one to decide on


Video memoryVideo memory

Video cards now come with either 128mb, Video cards now come with either 128mb, 256mb or 512mb of memory located on 256mb or 512mb of memory located on the video card used for textures. Games the video card used for textures. Games and applications today usually require a and applications today usually require a graphics card with at least 128mb to store graphics card with at least 128mb to store more advanced detailed textures. Any more advanced detailed textures. Any card with less than 128mb will have a card with less than 128mb will have a sufficient performance loss when dealing sufficient performance loss when dealing with large textures in today's softwarewith large textures in today's software


Consequences derived from Consequences derived from purchasing a video cardpurchasing a video card


Consequences of AGPConsequences of AGP

Having to settle for a less than spectacular video card Having to settle for a less than spectacular video card since all the high-end cards that are being produced are since all the high-end cards that are being produced are PCI-E. PCI-E. Can get a PCI-E card that performs substantially better Can get a PCI-E card that performs substantially better than a price equivalent AGP cardthan a price equivalent AGP card

i.e. $289 7800 GS (AGP) vs $309 7900GT (PCI-E)i.e. $289 7800 GS (AGP) vs $309 7900GT (PCI-E)

If you get a high-end AGP card then you are stuck with If you get a high-end AGP card then you are stuck with outdated technology. Since it is unlikely anymore high-outdated technology. Since it is unlikely anymore high-performance AGP cards will be released, you are limited performance AGP cards will be released, you are limited to what manufactures may decide to produce. You also to what manufactures may decide to produce. You also lose any chance of upgrading to a newer lose any chance of upgrading to a newer motherboard/processor since you cannot transfer the motherboard/processor since you cannot transfer the video card into a PCI-E based system.video card into a PCI-E based system.


Consequences of PCI-EConsequences of PCI-E

Likewise if you want to purchase a PCI-E card and your Likewise if you want to purchase a PCI-E card and your motherboard only supports AGP you will have to motherboard only supports AGP you will have to upgrade to a newer one that has one or more PCI-upgrade to a newer one that has one or more PCI-Express slots such as the nForce4 based motherboards.Express slots such as the nForce4 based motherboards.

Free to upgrade since PCI-E is common on all Free to upgrade since PCI-E is common on all motherboards being produced now. There is no need to motherboards being produced now. There is no need to worry about not being able to use your video card in your worry about not being able to use your video card in your

next setupnext setup


Works CitedWorks Citedhttp://www.wikipedia.org/wiki/Graphics_card http://www.wikipedia.org/wiki/Graphics_card http://en.wikipedia.org/wiki/Computer_display_standard http://en.wikipedia.org/wiki/Computer_display_standard http://www.cknow.com/refs/VideoDisplayStandards.html http://www.cknow.com/refs/VideoDisplayStandards.html Photo credits: Photo credits: http://www.mobygames.com/game/dig-dug/screenshots http://www.mobygames.com/game/dig-dug/screenshots http://i.jubii.dk/rd/dynamic/gallery/http://i.jubii.dk/rd/dynamic/gallery/http://users.adelphia.net/~amito/ http://psychosaurus.com/doom/images/ http://users.adelphia.net/~amito/ http://psychosaurus.com/doom/images/

http://computer.howstuffworks.com/pci-express.htmhttp://computer.howstuffworks.com/pci-express.htm by by Tracy V. WilsonTracy V. Wilsonhttp://computer.howstuffworks.com/agp.htm by http://computer.howstuffworks.com/agp.htm by Robert ValdesRobert Valdes and and Jeff TysonJeff Tyson


Display DevicesDisplay DevicesWhat is a display device?What is a display device?

Also called a Also called a displaydisplayAn output device An output device that visually that visually conveys text, conveys text, graphics, and video graphics, and video informationinformationInformation on a Information on a display device is display device is sometimes called sometimes called soft copysoft copy


Contains a cathode ray Contains a cathode ray tube (CRT), a large tube (CRT), a large sealed, glass screensealed, glass screenThe screen is coated with The screen is coated with tiny dots of phosphor tiny dots of phosphor materialmaterialA pixel, or picture element, A pixel, or picture element, is a single point in an is a single point in an electronic imageelectronic imageThree dots (red, blue, and Three dots (red, blue, and green) combine to make up green) combine to make up each pixeleach pixel

Display DevicesDisplay DevicesWhat is a CRT monitor?What is a CRT monitor?

CRT monitor screen

cathode ray tube


Display DevicesDisplay DevicesWhat are typical sizes for CRT monitors?What are typical sizes for CRT monitors?

15, 17, 19, 21, and 15, 17, 19, 21, and 22 inches22 inchesMonitor measured Monitor measured diagonally from one diagonally from one corner of the corner of the casing to the othercasing to the otherThe viewable size The viewable size is the diagonal is the diagonal measurement of measurement of the actual viewing the actual viewing area provided by area provided by the monitorthe monitor

screen size

viewable size


Display DevicesDisplay DevicesWhat is a liquid crystal display (LCD) monitor?What is a liquid crystal display (LCD) monitor?

A type of flat-panel displayA type of flat-panel display

Uses liquid crystals Uses liquid crystals between two sheets of between two sheets of material to present material to present information on a screeninformation on a screen

An electric current passes An electric current passes through the crystals which through the crystals which creates the images on the creates the images on the screenscreen


Display DevicesDisplay DevicesWhere are some features of LCD screens?Where are some features of LCD screens?

Lightweight and Lightweight and compactcompactConsumes less than Consumes less than one-third of the power one-third of the power than does a CRT than does a CRT monitormonitorCome in a variety of Come in a variety of sizessizesIdeal for notebook and Ideal for notebook and handheld computershandheld computers


800 x 600typically the

standard

Display DevicesDisplay DevicesWhat is display resolution?What is display resolution?

Describes the sharpness and clearness of an imageDescribes the sharpness and clearness of an image

Resolution of a display device stated as dots, or pixelsResolution of a display device stated as dots, or pixels

1280 x 1024maximum resolution

of most monitors

800 horizontal

pixels

600 vertical pixels

Total of 480,000 pixels on screen2048 x 1536

maximum for high-end monitors


Display DevicesDisplay DevicesWhat is dot pitch?What is dot pitch?

Another factor used to Another factor used to measure image claritymeasure image claritySometimes called pixel Sometimes called pixel pitchpitchThe distance between The distance between each pixel on a displayeach pixel on a displayThe smaller the The smaller the distance between the distance between the pixels, the sharper the pixels, the sharper the imageimage

Use a monitor with a dot pitch

of .29 millimeters or lower to

minimize eye fatigue


Should be fast enough to maintain a constant, flicker-free

image

A high-quality monitor will provide a refresh rate of at

least 75 hertz

Display DevicesDisplay DevicesWhat is refresh rate?What is refresh rate?

Another factor in a Another factor in a monitor’s qualitymonitor’s qualityAlso called vertical Also called vertical frequency or vertical frequency or vertical scan ratescan rateThe speed that a monitor The speed that a monitor redraws images on the redraws images on the screenscreenMeasured according to Measured according to hertz, which is the hertz, which is the number of times per number of times per second the screen is second the screen is redrawnredrawn

The image on the screen redraws itself 75 times in a second


Display DevicesDisplay DevicesWhat is a video card?What is a video card?

Converts digital output Converts digital output from the computer into from the computer into an analog video signalan analog video signalSends the signal Sends the signal through a cable to the through a cable to the monitormonitorControls how the Controls how the display device display device produces the pictureproduces the pictureAlso called a graphics Also called a graphics card or video adaptercard or video adapter


Step 1Step 1Step 2

Step 1Step 2

Step 3

Step 1Step 2

Step 4

Step 3

Step 1Step 2

Step 3

Step 4

Step 5

Step 2

Step 3

Step 4

Step 5

Step 6

Step 1Display DevicesDisplay Devices

How does video travel How does video travel from the processor to a from the processor to a CRT monitor?CRT monitor?

Step 1: The processor sends digital video data to the video card.Step 2: The video card’s digital-to-analog converter (DAC) converts the digital video data to an analog signal.

Step 3: The analog signal is sent through a cable to the CRT monitor.Step 4: The CRT monitor separates the analog signal into red, green, and blue signals.Step 5: Electron guns fire the three color signals to the front of the CRT.Step 6: An image displays on the screen when the electrons hit phosphor dots on the back of the screen.

Documents

COMP 364 Jess Role @ UEAB 2006 AGP Video Cards. COMP 364 Jess Role @ UEAB 2006 What is a Graphics Card? A video card or graphics card is the name we give