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A GeForce 6600 Series card by PNY
Motherboard via one of:
Display via one of:
A video card (also called a video adapter, display card, graphics card, graphics board, display adapter or graphics adapter) is an multi-monitor).
Video hardware can be integrated into the motherboard or (as with more recent designs) the CPU, but all modern motherboards (and some from the 1980s) provide expansion ports to which a video card can be connected. In this configuration it is sometimes referred to as a video controller or graphics controller. Modern low-end to mid-range motherboards often include a graphics chipset manufactured by the developer of the northbridge (e.g. an AMD chipset with Radeon graphics or an Intel chipset with Intel graphics) on the motherboard. This graphics chip usually has a small quantity of embedded memory and takes some of the system’s main RAM, reducing the total RAM available. This is usually called integrated graphics or on-board graphics, and is usually low in performance and undesirable for those wishing to run 3D applications. A dedicated graphics card on the other hand has its own Random Access Memory or RAM and Processor specifically for processing video images, and thus offloads this work from the CPU and system RAM. Almost all of these motherboards allow (PCI-E) the disabling of the integrated graphics chip in BIOS, and have an AGP, PCI, or PCI Express(PCI-E) slot for adding a higher-performance graphics card in place of the integrated graphics.
A modern video card consists of a printed circuit board on which the components are mounted. These include:
 Graphics Processing Unit
A graphics processing unit (GPU), also occasionally called visual processing unit (VPU), is a specialized frame buffer intended for output to a display.
 Heat Sink
A heat sink is mounted on high performance graphics cards. A heat sink spreads out the heat produced by the graphics processing unit evenly throughout the heat sink and unit itself. The heat sink commonly has a fan mounted as well to cool the heat sink and the graphics processing unit.
 Video BIOS
The firmware contains the basic program, which is usually hidden, that governs the video card’s operations and provides the instructions that allow the computer and software to interact with the card. It may contain information on the memory timing, operating speeds and voltages of the graphics processor, RAM, and other information. It is sometimes possible to change the BIOS (e.g. to enable factory-locked settings for higher performance), although this is typically only done by video card overclockers and has the potential to irreversibly damage the card.
 Video memory
||This article’s factual accuracy is disputed. (December 2011)|
|Type||Memory clock rate (MHz)||Bandwidth (GB/s)|
|DDR||166 – 950||1.2 – 3.04|
|DDR2||533 – 1000||8.5 – 16|
|GDDR3||700 – 2400||5.6 – 156.6|
|GDDR4||2000 – 3600||128 – 200|
|GDDR5||900 – 5700||130 – 230|
The memory capacity of most modern video cards ranges from 128 MB to 8 GB. Since video memory needs to be accessed by the GPU and the display circuitry, it often uses special high-speed or multi-port memory, such as VRAM, WRAM, SGRAM, etc. Around 2003, the video memory was typically based on DDR technology. During and after that year, manufacturers moved towards DDR2, GDDR3, GDDR4 and GDDR5. The effective memory clock rate in modern cards is generally between 1 GHz and 6.3 GHz .
Video memory may be used for storing other data as well as the screen image, such as the vertex buffers, and compiled shader programs.
The SCART etc.) only. These require a RAMDAC, but they reconvert the analog signal back to digital before they can display it, with the unavoidable loss of quality stemming from this digital-to-analog-to-digital conversion.
The most common connection systems between the video card and the computer display are:
 Video Graphics Array (VGA) (DE-15)
Analog-based standard adopted in the late 1980s designed for CRT displays, also called VGA connector. Some problems of this standard are electrical noise, image distortion and sampling error evaluating pixels.
 Digital Visual Interface (DVI)
Digital-based standard designed for displays such as flat-panel displays (native resolution. It is worth to note that most manufacturers include DVI-I connector, allowing(via simple adapter) standard RGB signal output to an old CRT or LCD monitor with VGA input.
 Video In Video Out (VIVO) for S-Video, Composite video and Component video
Included to allow the connection with mini-DIN connector variations, and the VIVO splitter cable generally comes with either 4 connectors (S-Video in and out + composite video in and out), or 6 connectors (S-Video in and out + component PB out + component PR out + component Y out [also composite out] + composite in).
 High-Definition Multimedia Interface (HDMI)
An advanced digital audio/video interconnect released in 2003 and is commonly used to connect HDCP.
An advanced license- and royalty-free digital audio/video interconnect released in 2007. DisplayPort intends to replace VGA and DVI for connecting a display to a computer.
 Other types of connection systems
|Composite video||Analog system with lower resolution; it uses the RCA connector.|
|Component video||It has three cables, each with RCA connector (YPBPR for analog component); it is used in projectors, DVD players and some televisions.|
|DB13W3||An analog standard once used by IBM.|
|DMS-59||A connector that provides two DVI or VGA outputs on a single connector. This is a DMS-59 port.|
 Motherboard interface
Chronologically, connection systems between video card and motherboard were, mainly:
- S-100 bus: designed in 1974 as a part of the Altair 8800, it was the first industry-standard bus for the microcomputer industry.
- ISA: Introduced in 1981 by IBM, it became dominant in the marketplace in the 1980s. It was an 8 or 16-bit bus clocked at 8 MHz.
- Macintosh II, it was a 32-bit bus with an average bandwidth of 10 to 20 MB/s.
- MCA: Introduced in 1987 by IBM it was a 32-bit bus clocked at 10 MHz.
- EISA: Released in 1988 to compete with IBM’s MCA, it was compatible with the earlier ISA bus. It was a 32-bit bus clocked at 8.33 MHz.
- VLB: An extension of ISA, it was a 32-bit bus clocked at 33 MHz.
- PCI: Replaced the EISA, ISA, MCA and VESA buses from 1993 onwards. PCI allowed dynamic connectivity between devices, avoiding the manual adjustments required with jumpers. It is a 32-bit bus clocked 33 MHz.
- Sun Microsystems in 1995. It had a 64-bit bus clocked at 67 or 83 MHz.
- toys, USB displays and display adapters exist.
- AGP: First used in 1997, it is a dedicated-to-graphics bus. It is a 32-bit bus clocked at 66 MHz.
- PCI-X: An extension of the PCI bus, it was introduced in 1998. It improves upon PCI by extending the width of bus to 64-bit and the clock frequency to up to 133 MHz.
- PCI Express: Abbreviated PCIe, it is a point to point interface released in 2004. In 2006 provided double the data-transfer rate of AGP. It should not be confused with PCI-X, an enhanced version of the original PCI specification.
In the attached table is a comparison between a selection of the features of some of those interfaces.
|Bus||Width (bits)||Clock rate (MHz)||Bandwidth (MB/s)||Style|
|PCI||32 – 64||33 – 100||132 – 800||Parallel|
|PCIe x1||1||2500 / 5000||250 / 500||Serial|
|PCIe x4||1 × 4||2500 / 5000||1000 / 2000||Serial|
|PCIe x8||1 × 8||2500 / 5000||2000 / 4000||Serial|
|PCIe x16||1 × 16||2500 / 5000||4000 / 8000||Serial|
|PCIe x1 2.0||1||500 / 1000||Serial|
|PCIe x4 2.0||1 * 4||2000 / 4000||Serial|
|PCIe x8 2.0||1 * 8||4000 / 8000||Serial|
|PCIe x16 2.0||1 × 16||5000 / 10000||8000 / 16000||Serial|
|PCIe X1 3.0||1||1000 / 2000||Serial|
|PCIe X4 3.0||1 * 4||4000 / 8000||Serial|
|PCIe X8 3.0||1 * 8||8000 / 16000||Serial|
|PCIe X16 3.0||1 * 16||16000 / 32000||Serial|
 Power demand
As the processing power of video cards has increased, so has their demand for electrical power. Current high-performance video cards tend to consume a great deal of power. While CPU and  Modern video cards with a power consumption over 75 Watts usually include a combination of six-pin (75W) or eight-pin (150W) sockets that connect directly to the power supply.
Video cards come in 2 sizes, to allow adding a videocard to even 
 See also
- GPU and graphics card designers
- ATI Crossfire – ATI’s proprietary mechanism for scaling graphics performance
- Computer display standards – detailed list of standards like SVGA, WXGA, WUXGA, etc.
- Feature connector
- Radeon – Examples of GPUs.
- AMD FireStream)
- Graphics hardware and FOSS
- Framebuffer – The computer memory used to store a screen image
- Mini-DIN connector
- List of video card manufacturers
- Scalable Link Interface – NVIDIA’s proprietary mechanism for scaling graphics performance
- Texture mapping – A means of adding image details to a 3D scene
- Video In Video Out (VIVO)
- Z-buffering – A means of determining visibility.
- ATI FireGL V8650.
- NVIDIA Quadro FX 5800.
- “Refresh rate recommended”. http://www.worldstart.com/tips/tips.php/1146.
- X-bit labs: Faster, Quieter, Lower: Power Consumption and Noise Level of Contemporary Graphics Cards
- Coding Horror Video Card Power Consumption
- Maxim Integrated Products. “Power-Supply Management Solution for PCI Express x16 Graphics 150W-ATX Add-In Cards”. http://www.maxim-ic.com/appnotes.cfm/an_pk/3605.
- Low profile video card
- Low-profile video cards
- Mueller, Scott (2005) Upgrading and Repairing PCs. 16th edition. Que Publishing. ISBN 0-7897-3173-8
|Wikimedia Commons has media related to: Graphics card|
- Graphics Card Comparisons, Performance, and Specifications
- How Graphics Cards Work at HowStuffWorks