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Video Cards
Video Cards
CS431 Class Presentation
CS431 Class Presentation
Ashish Bhat (02007025)
Ashish Bhat (02007025)
Nilesh Meshram (02007027)
Nilesh Meshram (02007027)
Introduction
Introduction
Interface between computer and a display device
Interface between computer and a display device
Unless a computer has graphics capability built into
Unless a computer has graphics capability built into
the motherboard, the video card is required.
the motherboard, the video card is required.
The CPU, working in conjunction with software
The CPU, working in conjunction with software
applications, sends information about the image to
applications, sends information about the image to
the video card. The video card decides how to use
the video card. The video card decides how to use
the pixels on the screen to create the image. It
the pixels on the screen to create the image. It
then sends that information to the monitor through
then sends that information to the monitor through
output interface.
output interface.
The Evolution of Video Cards
The Evolution of Video Cards
IBM introduced the first video card in 1981 called a
IBM introduced the first video card in 1981 called a
Monochrome Display Adapter (MDA), which
Monochrome Display Adapter (MDA), which
provided text-only displays of green or white text
provided text-only displays of green or white text
on a black screen.
on a black screen.
Presently, the minimum standard for new video
Presently, the minimum standard for new video
cards is Video Graphics Array (VGA), which allows
cards is Video Graphics Array (VGA), which allows
256 colors.
256 colors.
With high-performance standards like Quantum
With high-performance standards like Quantum
Extended Graphics Array (QXGA), video cards can
Extended Graphics Array (QXGA), video cards can
display millions of colors at resolutions of up to
display millions of colors at resolutions of up to
2040 x 1536 pixels.
2040 x 1536 pixels.
Components in a Video Card
Components in a Video Card
Graphics Controller / Graphic Processing
Graphics Controller / Graphic Processing
Unit (GPU)
Unit (GPU)
Video Memory (RAM)
Video Memory (RAM)
Digital-to-analog Converter (DAC)
Digital-to-analog Converter (DAC)
Attribute Controller
Attribute Controller
Output Interface - RGB, Composite, DVI
Output Interface - RGB, Composite, DVI
BUS Interface
BUS Interface
BIOS
BIOS
Components in a Video Card
Components in a Video Card
Video Card - GPU
Video Card - GPU
Similar to CPU but designed specifically to
Similar to CPU but designed specifically to
perform complex mathematical and
perform complex mathematical and
geometric calculations necessary for
geometric calculations necessary for
graphics rendering
graphics rendering
Less congestion on the system bus
Less congestion on the system bus
Reduction in the workload of CPU
Reduction in the workload of CPU
Video Card - GPU
Video Card - GPU
Operations: bitmap transfers, painting,
Operations: bitmap transfers, painting,
window resizing and repositioning, line
window resizing and repositioning, line
drawing, font scaling and polygon drawing
drawing, font scaling and polygon drawing
etc.
etc.
Some GPUs have image enhancement
Some GPUs have image enhancement
algorithms built-in
algorithms built-in
–
e.g. 3D edge smoothening
e.g. 3D edge smoothening
Video Card - GPU
Video Card - GPU
Some of the latest
Some of the latest
GPUs have more
GPUs have more
transistors than
transistors than
average CPU and
average CPU and
produce a lot of heat.
produce a lot of heat.
Heat-sinking and fan
Heat-sinking and fan
cooling are required
cooling are required
Video Card - Memory
Video Card - Memory
Video Memory (RAM) is used for:
Video Memory (RAM) is used for:
–
Frame Buffering: holding completed imaged until
Frame Buffering: holding completed imaged until
its time to display them
its time to display them
–
As the GPU creates images, the image
As the GPU creates images, the image
information is stored in this video memory frame
information is stored in this video memory frame
buffer as a digital bitmap
buffer as a digital bitmap
–
Total amount of video memory installed may not
Total amount of video memory installed may not
be needed for a particular resolution, the extra
be needed for a particular resolution, the extra
memory often used for caching information for
memory often used for caching information for
the graphics processor
the graphics processor
for example, the caching of commonly used
for example, the caching of commonly used
graphical items, such as text fonts and icons
graphical items, such as text fonts and icons
Unified memory architecture: Use of portion of
Unified memory architecture: Use of portion of
system memory as frame buffer
system memory as frame buffer
- Cost reduction
- Cost reduction
- Inferior graphics performance
- Inferior graphics performance
The greater number of colors, or higher the
The greater number of colors, or higher the
resolution, the more video memory will be required.
resolution, the more video memory will be required.
However, since it is a shared resource reducing one
However, since it is a shared resource reducing one
will allow an increase in the other
will allow an increase in the other
Video Card - Memory
Video Card - Memory
[...]... 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 - VRAM - WRAM - EDO - SDRAM - DDRRAM - RDRAM ... 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 Card - Attribute... 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...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 Video Cards - Resolution and Color depth Resolution - specified... 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... Resolution Color Graphics 640x200 None Adapter 1984 Standard No of colors 160x200 16 Enhanced Graphics 640x350 16 from 64 Adapter 1987 Video Graphics 640x480 16 from 262,144 Array 1990 VGA 320x200 256 XGA Extended Graphics Array 1024x768 16.7 million SXGA Super Extended 1280x1024 Graphics Array 16.7 million UXGA Ultra XGA 16.7 million 1600x1200 Output Interface - RGB Most CRT monitors require... 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 . buffer
- Cost reduction
- Cost reduction
- Inferior graphics performance
- Inferior graphics performance
The greater number of colors, or higher the. (VGA), which allows
256 colors.
256 colors.
With high- performance standards like Quantum
With high- performance standards like Quantum
Extended Graphics