Computer video card and its purpose
A video card is that device with which the image is displayed on the monitor. Those. without a video card, we won’t see any text or images on the screen, and in general, computer operation without a video card is impossible.
There are two types of video cards: external video cards (discrete) and built-in (onboard from English “On board” – on the board). Let’s look at these concepts together in more detail. There are two monopolists on the external video card market now. These are California-based Nvidia and Canadian ATI Technologies. In 2006, the latter was also purchased by the American processor company AMD (Advanced MIcro Devices). Now AMD is actively selling its graphics accelerators under the promoted ATI, in due time, brand “Radeon”.
Here’s what an external (discrete) entry-level video card from ATI-AMD might look like:
The numbers in the photo indicate:
GPU cooling fan heatsink
PCI-Express slot used to insert the card into the motherboard
(3-4) Video outputs VGA and DVI, respectively (now there is a massive transition to the new digital standard – HDMI)
Note: GPU (Graphics Processing Unit or graphic processing device) – the graphics processor of the video card (its core).
Let’s take a closer look: the core of the video card (in some simplification) is the same chip as the core of the central processor. It only deals with its specific tasks – displaying an image (any) on the user’s screen. Starting from text output and ending with the processing of three-dimensional scenes of your favorite computer game.
The GPU chip itself at the factory (using the BGA mounting method) is soldered to the PCB of the external video card (red “plastic” in the figure above), the radiator is tightly (either glued or screwed) on the top to remove heat and already onto the radiator itself – a fan (cooler) for dispersing hot air. As you can see, structurally, all this is very similar to a processor with its system cooling.
An external graphics card is connected to the motherboard through a dedicated connector (slot). For each generation of video cards, it is different (depending on the time of issue of the card).
This statement is true for almost the entire range of computer components. In this case, here you can quite easily determine purely visually “by eye”. The first video cards were installed in ISA (Industry Standard Architecture) connectors, they were replaced by a PCI connector (Peripheral Component Interconnect – literally: interconnection of peripheral components), then – AGP (Accelerated Graphics Port – accelerated graphics port) and now we have a bus and, accordingly, a PCI-Express slot. Moreover, its different versions (revisions) are physically and electrically compatible with each other, but differ only in the bandwidth (width) of the data bus connecting the video card and the motherboard.
Through video outputs on the card, it is physically connected to the monitor (or TV). Here, again, it all depends on the standard supported by your monitor / TV.
For example, a VGA connector (number 1 in the photo above) transmits a signal in analog form. The DVI standard (number 2) implies exclusively digital signal transmission (without any additional conversions). The new HDMI standard, along with cable images, can also transmit sound. The acronym HDMI stands for “High Definition Multimedia Interface” – a high-definition multimedia interface (high quality).
I think you caught the main idea: we look at what we have (which outputs are available), we check with what we want to connect to the subject “it will fit, it will not fit”, we think the presence of any connectors we may need in the future – we take it “for growth” 🙂 And, of course, do not forget about adapters, with which an external video card can be connected to an image output device: DVI-VGA or HDMI-VGA (no longer an adapter, but a full-fledged video signal converter).
I would like to say a few words about modern video cards, which require additional power to work, fed to them directly from the computer’s power supply.
The situation here is as follows: any external video card for a computer (whether it is PCI, AGP, or PCI-Express) receives power directly from the connector on the motherboard in which it is installed. For example, the maximum power in watts that an AGP connector can provide is 42 W, PCI-Express version 1.1 is 76 W (watts), respectively.
As you know, many modern external graphics cards (especially at maximum loads) consume much more power. It is because of this that they came up with an additional power connector.
Here’s what these connectors might look like:
Complete with such a graphics accelerator, there must be a special adapter that connects one of the standard “molex” power supply connectors and an additional card power input.