What is a computer graphics card

Sometimes on the web you can see the question "what is a video card". Although it seems banal, nevertheless, the person who decided to understand it, deserves respect, as it seeks to understand the device of the computer.

Everyone knows that the work of all computing devices is based on the binary representation of information. Who has ever seen a sequence of zeros and ones printed on paper or a monitor screen, knows that it is almost impossible to understand anything there. This is easy to explain, because all these numbers - a kind of micro-commands for transistors. What is the connection of all of the above with the question of what a video card is? Immediate! What we see on the screen of the monitor is the internal computer streams of digital data converted into recognizable symbols. The task of such a transformation is precisely assigned to the video card.

Let's define the notion "what is a video card". A video adapter (video card) is a device designed to display graphic information on a monitor screen (by analogy, how the printer displays on paper). Moreover, not any digital data, but in a certain way prepared. For example, if you try to display the digital stream of hard disk commands via a video card, then nothing happens. All internal data is preprocessed by the central processor for each target device: the addresses are set to them, the bus is specified, etc.

But all of the above applies only to the software component, therefore, considering this one-sidedly, it is impossible to answer in detail the question "what is a video card". Physically, it is an expansion board that plugs into the corresponding socket (slot) of the motherboard (mainboard). Almost all modern video adapters are designed for PCI Express bus.

The board contains the following components: graphics processor, controller, video card memory (RAM and ROM), bus connector and output connectors, DAC, cooling system, accessories. In some models, the list can be expanded with additional components.

The parameters of the video card are largely determined by the installed graphics processor. Currently, their production is engaged in two companies - AMD (ATI) and NVidia. The share of others is small, although the well-known Intel also tries to claim its part of the market.

The video card processor (GPU) is creating images from the data provided by the applications. The number of transistors in it exceeds this figure for central processors, which allows to speak about its unprecedented speed. By the way, this is why it is increasingly possible to meet specialized programs that perform calculations on GPU capacities. Yes, and gaming applications through the provided capabilities (PhysX, DirectCompute) have long learned to use its resources for mathematical calculations, not related to the formation of images.

The controller is assigned the task of interacting with memory, as well as external and internal buses. The bit width of the internal bus is the second most important indicator of performance after the GPU. Models with 64, 128, 256 and more bits are now common. To buy less than 128 is not recommended.

Memory on the video card is needed for storing and processing images created by the GPU, before being directly displayed. It is characterized by the type of installed microcircuits (DDR - GDDR5) and volume. The fastest solutions come with GDDR5. Modern games require at least 512 MB of volume (depends on the settings).

Each card, as already indicated, is calculated for a specific bus. Now PCI Express 16 is universally used. Sometimes there are PCI, but their cost is higher. Several years ago, AGP bus reigned in computers, but Intel, as always, aborted it in time.

The output connector defines the interface through which the signal can be sent to the monitor. There are several of them: obsolete D-SUB, digital DVI, modern HDMI, Display Port, etc.

Sometimes the video card is part of the CPU, in this case it uses the system memory, and the output connector is decoupled on the motherboard. Performance of such solutions is inferior to external analogues.