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