The images that show up on your monitor are made of many tiny dots known as pixels. In the settings of the most common resolution, a screen displays more than a million pixels, and it is left for the computer to decide what to do with each pixel to form an image.
To do this, there is a need for a translator (a translator is something that will take binary data from the CPU and convert it into a picture that you can see).
Usually, the translation happens on the graphics cards, unless a computer comes with graphics capability already built into the motherboard.
The job of a graphics card is a complex one, but it comes with a few principles and components that are not difficult to understand. What we have done in this article is to take a look at the essential elements of a video card and the job they do.
Also, we will examine the factors that work together to form a graphics card that is both fast and efficient.
The best way to understand what a graphics card is it to think of a computer as a firm with an art department, which is the graphics card. When people working in the company need a piece of artwork, all they have to do is send a request to the company’s art department.
The art department has to decide how to create the image and how to puts it on paper. What becomes the result is the transformation of someone’s idea into an actual, viewable picture.
The principles above are the same ones a graphics card works along. The CPU, working together with software applications, will send information about an image to the graphics card.
Then, the graphics card will decide how to use the pixels sent to the screen to make the image. The graphics card then sends the information to the monitor via a cable.
Making an image from binary data is a very demanding process. For graphics are to make a 3D image, it must first create a wireframe out of straight lines. After that, it rasterizes the image (this means that it fills in the remaining pixels).
Lighting, color, and texture is also added. For fast-paced games, the process has to be carryout by about sixty times every second. Without a graphics card to carry out the necessary calculations, there will be too much workload for the computer to deal with.
A graphics card accomplishes this task with the aid of four main components:
- A motherboard connection for power and data
- A processor to help with deciding what to do with individual pixel on the screen
- Memory to save information about individual pixel and to temporarily save completed pictures
- Connection to a monitor so that you can view the final result
Next, we will take a look at the processor and memory in detail.
Just like a motherboard, the graphics card is a printed circuit board that harbor a RAM and processor.
It also comes with an input/output system (BIOS) chip that stores the card’s settings and carry’s out diagnostics on the memory, input, and output at the startup. The processor of a graphics card, known as a graphics processing unit (GPU), is a lot like a computer’s CPU.
However, a GPU is designed especially for carrying out the complex geometric and mathematical calculations that are required for graphics rendering. A fun fact is that some of the fastest GPUs come with more transistors than the average CPU.
Because a GPU produces so much heat, it is usually situated under a fan or a heat sink.
In addition to a GPU’s processing power, it makes use of special programming to assist it with analyzing and use data.
ATI and Nvidia are the producers of the vast majority of GPUs available on the market, and both companies are known to have developed their unique enhancements for GPU performance. To improve image quality, the processors involved use:
- Full scene anti-aliasing (FSAA), which works to smoothe the edges of a 3-D object
- Anisotropic filtering (AF), which is meant to make images look crisper
Individual companies have also developed specific techniques to assist the GPU to apply shading, colors, textures, and patterns.
As the GPU creates images, it needs somewhere to hold completed pictures and information. It makes use of the card’s RAM for this function, storing data about individual pixels, its color, and where it is located on the screen.
Part of the RAM can also serve as a frame buffer, which means that it saves completed images until it is time for them to be displayed. Typically, a video RAM functions at very high speeds and comes with is dual port, which means that the system can read from it and also write to it.
The RAM is connected directly to the digital-to-analog converter, known as the DAC. This converter, also known as the RAMDAC, interprets the image into an analog signal that can be used by the monitor. Some cards come with multiple RAMDACs, which can better the performance and support more than a single monitor.
The RAMDAC sends the final picture to the monitor via a cable. We will take a quick look at this connection as well as other interfaces in the section below.
Graphics cards are connected to the computer via the motherboard. The motherboard is what supplies power to the graphics card and allows it to communicate with the CPU.
For newer graphics cards, there is often a need for more control than can be provided by the motherboard, so they also possess a direct connection to the power supply of the computer.
Connections to the motherboard usually occur through one of three interfaces:
- Peripheral component interconnect (PCI)
- Advanced graphics port (AGP)
- PCI Express (PCIe)
The PCI Express is the most recent of the three and offers the most fast transfer rates between the graphics card and motherboard. A PCIe also provides support for the use of up to two graphics cards in a single computer.
Most graphics cards come with two monitor connections. Usually, one is a DVI connector that offers support to the LCD screens, and the second is a VGA connector that offers supports CRT screens.
For some graphics cards with two DVI connectors instead. However, that does not rule out making use of a CRT screen; a CRT screen can connect to DVI ports via an adapter.
There was a time when Apple made monitors that made use of the proprietary Apple Display Connector (ADC). Even though these monitors are very much in use, more recent Apple monitors make use of a DVI connection.
Most individuals make use of only one of their two monitor connections. Those who need to make use of two monitors can buy a graphics card with two head capability, which shares the display between both screens.
A computer that has two dual head, PCIe-enabled video cards can theoretically serve four monitors. Apart from connections for the monitor and motherboard, some graphics cards offer connections for:
- TV display: TV-out or S-video
- Digital cameras: FireWire or USB
- Analog video cameras: Vivo or video in/video out
- Some cards even incorporate TV tuners.
Choosing a very Good Graphics Card
It is easy to spot a top-of-the-line graphics card. It comes with lots of memory and a high-speed processor. Most times, it is also much more visually appealing than any other thing that is intended to find its way inside a computer’s case.
Many high-performance video cards are either illustrated or come with decorative fans or heat sinks. But a high-end card offers its user more power than is even required.
People who make use of their computers mainly for e-mail, Web surfing, or word processing, can find all the needed graphics support on a motherboard that has integrated graphics.
A mid-range card is just enough for most casual gamers. Those who may need the power of a high-end card are gaming enthusiasts and individuals who do a lot of 3-D graphic work.
A tremendous overall measurement of the performance of a card is the state of its frame rate, which is measured in frames per second (FPS). The number of images that can be displayed by the card per second is what is called the frame rate.
The human eye has the capability to process around 25 frames per second; however, fast-action games need a frame rate of nothing less than 60 FPS to offer smooth scrolling and animation. The components of the frame rate are:
Vertices or triangles per second: 3-D images are composed of triangles or polygons. This measurement of these shapes describes how fast the GPU can calculate the full polygon or the vertices that define it. Generally, it describes how quickly the card forms a wireframe image.
Pixel fill rate: This is a measurement that describes the number of pixels that the GPU can process in a second, which is interpreted to how fast it can rasterize the image.
The hardware of the graphics card has a direct effect on its speed. Below are the hardware specifications that majorly affects the card’s speed, as well as the units in which they are measured:
- Size of the memory bus (bits)
- GPU clock speed (MHz)
- Memory clock rate (MHz)
- Amount of available memory (MB)
- RAMDAC speed (MHz)
- Memory bandwidth (GB/s)
The CPU of the computer and the motherboard also play a role, since a very fast graphics card can not compensate for the inability of a motherboard to deliver data at a reasonable speed.
Similarly, the connection of the card to the motherboard and the rate at which it can obtain instructions from the CPU has an effect on its performance. Looking to purchase one? Checkout Amazon.