The graphics card, also known as video card, video adapter, graphics-accelerator card, or display adapter, is first of all the connection between the computer and its display device. It ensures that the calculations carried out by your pc actually appear on your display. Your display device is actually physically connected by the graphics card of your computer. Graphics cards come in various shapes and sizes, ranging from very small to giants that have dimensions of 27cm by 8cm (lenght and width) . This large difference in size (and price) can be explained by the second function of the graphics card...

This second function can be found in the "accelorator" part of the full name; graphics accelerator card. This basically means that the graphics card assists the processor with its calculations by taking over some of the load. The more expensive cards are able to execute a higher number calculations and are therefore faster. The strength of a graphics card lies in its ability to processes a lot of different calculations at the same time, as oppossed to a processor which is designed to proces only 1 string of data. This is especially important when you play video games. Due to it's paralel power, the latest graphic cards have a computing power of no less than 10 times the fastest processor. It is not hard to understand that this card plays an increasingly important role in the computer.

Intel and AMD

Noways there are 2 large brands for graphics cards, AMD Ati and Nvidia. The first can be recognised by the Radeon HD added to all model numbers (example: AMD Ati Radeon HD 4850), the latter is known for its Geforce series (example: Nvidia Geforce GTX260). In the shop you will notice several different brands, for example an Asus Geforce 9800GT. The cause of this different name lies in the fact that the two major brands mentioned earlier (Ati and Nvidia) only develop and produce the graphics cards. There is a thrid step required before you can buy the cards, which is adding the manual, creating good looking packaging, adding stickers, cables and a driver CD so it can be sold and displayed in the retail stores all over the world. Examples of these brands are Asus, MSI, XFX, Club 3D, Saphire, etc. The underlying technology for these different brand, the chip, are all so similar to the reference design created by AMD Ati or Nvidia. However some manufacturers make some minor adjustments. For example, the cooler or the standard clock speeds (MHz) can be increased, often these modified cards are called Extreme, OC or TOP editions.

Points of attention

Interface
Not every graphics cards wil fit in your computer system. There are various interfaces and only compatible interfaces will result in a working graphics card. Easier said; there is another slot on the motherboard where the card simply can not fit. The function of this interface is the facilitation of communication between the graphics card and the processor. Through the interface these parts "talk" with each other. The more calculations are performed the more information there will be exchanged, therefore a higher capacity will be required, hence the existence of different interfaces.

AGP
This is the old standard and consists of AGP1x, 4x and 8x. If yo have this slot your purchasing options will be limited, pretty much the entire industry has shifted to the new PCI-Express slots. However, it is still possible to purchase some cards suitable for agp (Nvidia Geforce 7600GS and 7600GT, AMD ATI Radeon ????). The bandwidth of this slot is between 264MB (AGP 1x) and 2000 MB (AGP 8x). Only PCs from before the year 2000 possibly have have AGP 1x or 2x.
PCI-Express
Since 2004, PCI-Express (PCI-E). With a bandwidth of 4000-8000 MB / s interface that doubled the capacity of AGP. This new interface allows the graphics card designers to create increasinly fast products without running into limitation in terms of avaiable bandwith between cpu-gpu and cpu-memory.

Powerusage
A second concern regarding your choice of graphic cards is power consumption. The cheaper graphics cards can be placed in the appropriate slot will operate without any problems. The faster, gaming, cards have additional power jacks. These jacks provide the graphics card with additional power. Without this additional power, the card and therefore the computer, will not function properly. Hence it is very important for enough power to be available. The choice of graphics card incfluences the choice of power supply unit. On the website of the manufacturers you can find the so-called "minimum requirements", these show how much watts your power supply unit should have (often ranging from 350W to 450W). PcInside offers more details at the power supply section.

Graphics card connections:
rear connections graphics card

1 S-video (tv connection)
2 DVI (modern displays, digital connection)
3 VGA (older displays, annalogue connection)
hdmi port

4 Display port (A relatively new development is the so-called display port or HDMI. HDMI introduced a new standard in 2006 for the transfer of digital pictures and sound (similar to DVI but sound included, so less cables required).

SLI and Crossfire (X)

In short: sli and crossfire are bout combining multiple graphics cards so in order to increase performance. SLI was developed by Nvidida, Crossfire by AMD / ATI. For more information see http://pcinside.info/nl/grafische-kaart/31-sli-en-crossfire.html (Only in dutch untill translated).

Performance Overview

Graphics cards come in many shapes and sizes. The following charts help to provide an overview on the basis of both performance and power consumption.