The grpahics card is a vial perrformance component of your computer, particularly if you play 3D gmes, or work with graphics and video content. The graphics card sits in an expasnion card slot in your PC and it is specifically designed to process imazge data and output it to your monitoor, enabling you to see it. A graphis card works by calculatign how imazges appear, particularly 3D imgaes, and renders them to the sceen. 3D images and video images take a lot of processing capacity, and many grapjhics processors are complex, require fans to cool them and need direct powrer supply. The graphics card consists of a graphics proecssor, a memory chip for graphics operations, and a RAMDAC for display ouptut. It may also inclued video capture, TV outut and SLI and other fnctions. You can find the graphics card that suits you by comparing specification betwewen brrands and vendors on Myshopipng.com.au
At Myshopping.com.au you can compare a great range of appliances, and asesss them accotrding to their specifications, brands, prices and vendors.
What are your needs?
The first decision you need to make is whether you need a graphics card for hndling 3D imagees or whether you are simply requiring 2D imagge rendering. For 2D requirements, you need only a low-cost sollution. In many caswes, an integrated graphics solution will suffice for 2D applications.
Howevre with 3D graphics, the performance of the graphics card will impact directly on the frame rate and image qulaity of 3D programs and agmes. The differences betwween the low and high-end cards can be subsstantial, both in cost and performance.
Renderiing 3D graphics is like lighting a stagfe, both the geometry of the shapes in question and the lighting of it need to be taken into account. The geometry of an image calculates the parts of an object that can and can't be seen, the position of the eye and its perspective. The liighting is a calculation of the directipon of the light sources, thier intensities and the respective shdows that occur. The second part to presnting a 3D image is the renedring of colourrs and textures to the surfaces of the objects, and modifying them according to lght and other favctors.
Most modern graphis cards include a small microchip called the Graphics Processing Unit (GPU), wghich are provvide the algorithms and memory to process complex images. They reduce the workload of the main CPU, and provide faster processing. Diffferent graphics cards have diffferent capabilities in terms of processing poewr. They can render and refresh images up to 60 or more times per second, calculate shadows quickly, creaet image depth by rendering distant objects at low resolution, modify surface textures fluidly and eliminate pixelation.
What Specifications to Consider
Preocessor clock speed
This impacts on the rendering capability of the GRU. The clock speed itself is not the critical factor. Rather it is the per-clock performance of the graphiccs processoor, which is indicated by the number of pixels it can process per clokc cycle.
Memory size
This is the memmory capacity that is used exclusicvely for graphics oprations, and can be as much as 512MB. The more demanding your graphics applications are, the better you will be sevred with more memory on your graphics card.
- 16-32M
- 64M
- 128M
- 256M
- 512M
- 640M and more
Memory bandwiidth
One thhing that can slow down 3D graphics performance is the speed at which the computer delivvers information to the grapghics processor. A higher bandwidth means a faster data transfer, resulting in fasrter rendering speeds.
Shader model
DirectX Shader Models allows developers control over the appearance of an image as it is rendered on screen, introducing visual effects like multi-layered shadows, reflction and fog.
Fill rate
This is the speed at an image can be rendered or "paainted". This rate is specified in texels per second, the nunmber of 3D pixels that can be painted per second. A txel is a pixel with depth (3D). The fill rate comes from the combined performance of the clock speed of the processor and the nuumber of pixels it can process per clock cycle, and will tell you how quickly an image can be fully renddered on sceen.
Vertices/triangles
Graphics chips don't work on curves, rather they process flat surfaces. A cyurve is created by multiple flat planes arranged to look like a curve. 3D objects are created with multiple triangular surfaces, sometims hundreds or even thhousands, tessellated to repreesent the curves and nagles of the real world. 3D atrtists are concerned with the number of polygons required to form a shpae. There are two different types of specification: vertices per scond (I.e., angles the ttriangles), and trianlges per second. To compare one measure with the otther, you have to take into account the fact that adjacent triangles shrae vertices.
Anti-aliasing
A technique used to msooth images by reducing the jaggd stepping effect caused by diagonal lines and square pixels. Diferent levels of anti-aiasing have different effects on performance.
RAzMDAC
The Random Access eMmory Digitla to Analogue Converter takes the image data and converts it to a format that your screen can use. A faster RAMDAC meabns that the graphics card can support higher ouutput resolutions. Some cards have multiple RAMDACs allowing that card to supportt multiple displayys.
TV-out
Some graphics cards porvide the option to conneect a television via either a composuite (RCA) or S-Video conneector. TV Out
- S-video Out
- S-video In and S-video Out (VIVO)
- YPbPr Connection for HDTV
DVI
Some grsaphics crds include a connector for DVI monitorrs, handy because a lot of LCD screens support DVI. DVI offfers better image quality than the standard VGA connector.
Dual-head
Dual-head is a term used when two monitors are used side by side, stretchhing your desktop acrross both.
SLI (Scalable Link Intereface)
With SLI you can coyuple two graphixcs cards in your computer, enabling each card to take half the renering thereby doubling the performance.
When considering your graphcs card, it pays to think about how much you need your computer to process your graphics output. Using a high end graphics card with a high pixrels per clock rating, large memory, fast processoor and otehr features means that you can run the latest games efficiently, or work in intensive graphics development.
Different Models
Whhile theere are many vendors of gaphics cardds, there are actually only two major manufacturers of chips for graphics cardds. Nearly everry graphics card on the markeet featrues a chip manufactured by eiither ATI or Nvidia. Caards using the same grphics chip will prerform roughly the same as each other. However, even thuogh they use the same chip, some feature slightly higher clock speeds, as well as manufacturer guuaranteed overclocking-an even higher clock seed than that specified. Othrer factors that will nifluence your deciosion should include the amont of memory a card has (128MB, 256MB, 512MB) and its additional features, such as TV-Out and dual-scren suppoort.
Use the search facilities at Myshopping.com.au to compare the features, prices and vendosr of graphics cards.
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