The device of a modern video card. VGA-compatible video controller: what is it and how to fix problems with graphics adapters

Video card

Video card (also known as graphics card, graphics card, video adapter) (English videocard)- a device that converts an image stored in the computer's memory into a video signal for the monitor.

Usually the video card is an expansion card and is inserted into connector extensions, universal (ISA, VLB,PCI,PCI-Express) or specialized ( AGP), but it can also be built-in (integrated).

Modern video cards are not limited simple conclusion images, they have built-in graphics microprocessor, which can produce additional processing, relieving the central CPU computer. For example, all modern NVIDIA video cards and AMD( ATi) support OpenGL applications in hardware.

Video cards have following standards

On PS/2 computers, most of the video adapter circuitry is located on system board. This video adapter contains everything electronic circuits, necessary to support the VGA specification, on one full-size board with an 8-bit interface.

BIOS VGA is a program designed to manage VGA circuits. Through BIOS programs can initiate some VGA procedures and functions without accessing the adapter.

All VGA equipment provides display of up to 256 shades on the screen from a palette of 262,144 colors (256 KB). An analog monitor is used for this.

If problems arise when booting the system, it boots into safe mode, where the default is VGA adapter in 640x480 mode, 16 colors.

SuperVGA Super Video Graphics Array. Provides more a high resolution than the VGA standard. Supports operating modes with resolutions of 800:600, 1024:768, 1280:1024 pixels (or more) with simultaneous display of 2 in 4, 8, 16, 32 degrees of color.

With adapters SVGA various models from different manufacturers you can communicate through a single software interface VESA

Existing standard VESA on boards SVGA provides the use of almost all common image formats and color coding options, up to a resolution of 1280x1024 pixels with 16,777,216 shades (24-bit color coding).

A modern video card consists of the following parts:

Bios (Basic Input/Output System - basic system I/O). The video adapter BIOS contains basic commands, which provide an interface between the video adapter hardware and software. A BIOS that can be modified using software is called flash BIOS.

GPU(Graphics processing unit - graphics processing unit)- deals with calculations of the displayed image, relieving you of this responsibility CPU, performs calculations to process 3D graphics commands. Is the basis graphics card, the performance and capabilities of the entire device depend on it. Modern graphic processors are not much inferior in complexity to the computer's central processor, and often surpass it both in the number of transistors and in computing power, thanks to a large number universal computing units. However, the architecture GPU The previous generation usually involves the presence of several information processing units, namely: a 2D graphics processing unit, a 3D graphics processing unit, in turn, usually divided into a geometric kernel (plus a vertex cache) and a rasterization unit (plus a texture cache), etc.

Video controller- responsible for forming an image in video memory, gives commands RAMDAC to generate scanning signals for the monitor and processes requests from the central processor. In addition, there is usually an external data bus controller (for example, PCI or AGP), internal data bus controller and video memory controller. The width of the internal bus and video memory bus is usually larger than the external one (64, 128 or 256 bits versus 16 or 32); many video controllers also have built-in RAMDAC. Modern graphics adapters ( ATI, nVidia) usually have at least two video controllers that operate independently of each other and simultaneously control one or more displays each.

Video memory- acts as a frame buffer in which the image is stored, generated and constantly changed by the graphics processor and displayed on the monitor screen (or several monitors). Video memory also stores intermediate image elements invisible on the screen and other data. Video memory comes in several types, differing in access speed and operating frequency. Modern video cards are equipped with memory type DDR, DDR2, GDDR3, GDDR4 and GDDR5. It should also be borne in mind that in addition to the video memory located on the video card, modern graphics processors usually use part of the total system memory computer, direct access to which is provided by the video adapter driver via the bus AGP or PCIE.

Digital-to-analog converter (DAC, RAMDAC - Random Access Memory Digital-to-Analog Converter)- serves to convert the image generated by the video controller into color intensity levels supplied to an analog monitor.

Video ROM- a permanent storage device in which video BIOS are recorded, screen fonts, service tables, etc. ROM is not used directly by the video controller - only the central processor accesses it. The video BIOS, stored in ROM, ensures initialization and operation of the video card before loading the main operating system, and also contains system data that can be read and interpreted by the video driver during operation (depending on the method used sharing of responsibilities between the driver and the BIOS). On many modern maps electrically reprogrammable ROMs are installed ( EEPROM, Flash ROM), allowing the video BIOS to be rewritten by the user himself using a special program.

Cooling system- designed for preservation temperature regime video processor and video memory are within acceptable limits.

Very often, many computer and laptop users are faced with a rather unpleasant situation when, after reinstalling the operating system, discrete graphics accelerators installed directly on motherboard, disappear from the list of equipment presented in the “Device Manager”. In this case, instead of his own video card, the user sees some kind of video controller (VGA-compatible), which is marked with a yellow triangle with exclamation mark, which indicates that the driver for it is not installed. It also happens that the device does not seem to be marked as a device without a driver, but when launching the same games, serious problems begin, since they do not detect the required graphics adapter in the system. Why this happens and what actions can be taken in such a situation will be discussed further.

What is a video controller (VGA-compatible) in Device Manager?

Let's start with the fact that such a device, displayed in the list of equipment in Device Manager, is only indirectly related to a non-working graphics adapter. It’s just that the system detects the video card not as equipment on board, but as a certain virtual adapter. You can sometimes guess that this is an “iron” card by the fact that it is often indicated that it is a PCI video controller (VGA-compatible). PCI slot on the motherboard is precisely used for installing the graphics adapter. But, again, operating system sees it exclusively in the form virtual controller. Why?

Why is the wrong driver installed?

Problem incorrect installation driver is most often due to the fact that in its own database Windows required manager software it doesn’t find it for the graphics adapter (if anyone doesn’t know that during the initial installation and during the repeat installation, it uses exclusively its own driver databases).

Another very common situation is that when you reinstall the system without formatting system partition, the new installed OS may inherit errors from the old one, in which the graphics adapter drivers were not completely removed. Because of this, conflicts arise, and Windows itself installs the most suitable driver(as it seems to her), which is completely unsuitable for the functioning of the video card. True, you can also come across cases when the name of the video card seems to be displayed, but the system still shows that the driver for a card that is not present in the system is installed, namely a VGA-compatible video controller (NVIDIA, for example). For GeForce series devices, the reason lies precisely in the fact that outdated drivers were not completely removed.

How to reinstall the driver for a VGA-compatible video controller using the simplest method?

Despite such conflicts, the situation can be corrected quite simply.

First of all, in the “Device Manager”, select in the list VGA-compatible video controller and then through RMB menu select the driver update item, then specify the search for the system updated drivers. If this does not help, it is quite possible that the solution to the problem will be to roll back the driver (only if the corresponding button in the adapter properties section is active).

If this does not work, simply remove the device from the system and see how correctly the graphics adapter is detected after that (in some cases this happens instantly, and sometimes you may need to reboot the system).

Application of automated programs and databases

In the case of discrete graphics chips You can also use the driver disk that came with your purchase. Another good way to solve the problem is to visit the manufacturer’s official website, where you can find the latest software based on the video card model.

For NVIDIA and ATI adapters, manufacturers often provide additional programs, which also allow you to install or update (for example, NVIDIA Experience). If their use does not give anything, try using automated programs like DriverPack Solution or Driver Booster. The first utility contains its own database, which is much more more than that that Windows uses. And both update applications can access official resources manufacturers via the Internet to download and install updates. You can also use some informative utilities.

For example, in popular program Everest, when viewing information about image output devices for a video card, you can also download drivers.

What to do if the driver cannot be found?

If none of the above helped, but in the list graphics devices still, only a VGA-compatible video controller is present, use the “Device Manager”, through the RMB menu, call up the section of its properties, go to the details tab, from the drop-down list, set the display of equipment ID, copy or write down the most long string with identifiers DEV and VEN, then use it to search for a driver on the Internet, download the necessary software and install it yourself.

Note: If you receive errors when installing the found driver, you will have to remove all drivers manually. To do this, perform an analysis in Driver program Sweeper, delete all found elements, go to the registry (regedit), search for keys by the name of the video card manufacturer, delete everything that is found, restart the computer and try to install the drivers again. Sometimes the problem may be related to PhysX components, so it is possible that you will have to remove them too.

Sometimes a user needs to find out the model of his video card. And this can be done in several ways.

Via Device Manager

To open device Manager devmgmt.msc. Will open device Manager, in which click on the plus sign next to the category Video adapters. As you can see in the screenshot, the PC has ATI video card Radeon HD 6800 Series.

If instead of the model it says “Standard VGA graphic adapter", this means that the drivers for the video card have not been installed, so Windows cannot determine its type and model.

Likewise, if there is nothing in Video adapters, and in Other devices is “Video controller (VGA-compatible)” or “Standard VGA graphics adapter”, then this again means that official driver was not installed, so Windows installed its own driver. In this case, you can find out the driver version like this: click on Standard VGA graphics adapter(or Video controller (VGA compatible)») right key mouse and select Properties.

In it, switch to the tab Intelligence, and in the section Property change the item Device Description on Equipment ID.

In chapter Values right-click on the first line and select Copy.

Paste the copied text into a search engine. As you can see in the screenshot, the video card you are looking for is ATI Radeon HD 6800 Series.

Via Screen Options

To do this on empty space desktop, right-click and context menu select item Screen resolution. In the window that opens, find Extra options and open them. A window with properties will appear graphic editor. In chapter Intelligence about the adapter, find the item Adapter string. What is written next to it is the video card model.

Using the program

This program will help you find out the manufacturer of your video card, its model and driver version. And if the driver is missing, Everest will also tell you the official website of the graphics adapter manufacturer, where you can download its latest version.

Via DirectX Diagnostic Tool

To open DirectX Diagnostic Tool, press Win+R on your keyboard and in the window that appears, write dxdiag. Switch to tab Screen and in the section Device you will see the manufacturer and model of the video card.

Removing the system unit cover

Typically, video cards always indicate its manufacturer and model.

Nowadays, almost all computers are equipped with a discrete video card. By using of this device an image visible on the monitor screen is created. This component is far from simple, but consists of many parts that form a single working system. In this article we will try to talk in detail about all the components modern video card.

Today we will look at modern discrete video cards, because integrated ones have a completely different configuration and, basically, they are built into the processor. The discrete graphics adapter is presented as printed circuit board, which is inserted into the corresponding expansion connector. All components of the video adapter are located on the board itself in in a certain order. Let's take a closer look at all the components.

GPU

At the very beginning, we need to talk about the most important part in a video card - the GPU (graphics processing unit). From of this component The performance and power of the entire device depends. Its functionality includes processing graphics-related commands. The GPU takes over execution certain actions, thereby reducing the load on the CPU, freeing up its resources for other purposes. The more modern the video card, the greater the power of the GPU installed in it; it can even exceed the central processor due to the presence of many computing units.

Video controller

The video controller is responsible for generating the image in memory. It sends commands to digital-to-analog converter and processes CPU commands. A modern card has several built-in components: a video memory controller, an external and internal data bus. Each component operates independently of each other, allowing simultaneous control display screens.

Video memory

To store images, commands and intermediate elements not visible on the screen, a certain amount of memory is required. Therefore, each graphics adapter has a constant amount of memory. It happens different types, differing in their operating speed and frequency. Type GDDR5 on this moment is the most popular, used in many modern cards.

However, it is also worth considering that in addition to the memory built into the video card, new devices also use the RAM installed in the computer. To access it use special driver via PCIE and AGP bus.

Digital-to-analog converter

The video controller produces an image, but it must be converted into the desired signal with certain color levels. This process performs the DAC. It is built in the form of four blocks, three of which are responsible for RGB conversion(red, green and Blue colour), A last block stores information about the upcoming brightness and gamma correction. One channel operates at 256 brightness levels for individual colors, and in total the DAC displays 16.7 million colors.

Read Only Memory

The ROM stores the necessary screen elements, information from the BIOS and some system tables. The video controller is not used in any way with the permanent storage device; it is accessed only by the CPU. It is thanks to the storage of information from BIOS video card starts and functions even before the OS is fully loaded.

Cooling system

As you know, the processor and graphics card are the hottest components of a computer, so they need cooling. If in the case of a CPU the cooler is installed separately, then most video cards have a radiator and several fans built into them, which allows you to save relatively low temperature at heavy loads. Some powerful modern cards get very hot, so a more powerful water system is used to cool them.