Buying Guide - Graphics Cards

Types

EVEA graphics cardIn general terms, there are two main uses for a video card in a computer: 2D graphics and 3D graphics. Two-dimensional graphics are rendered on the screen via the video card for most tasks that the average computer user carries out, such as word processing, internet browsing and general desktop use, all of which require the use of a graphics card in order for the information on the screen to be presented.

With the advent of more complicated graphic effects in operating systems such as Windows 8 or Mac OS X, having a video card that is capable of rendering fast two dimensional effects is more important than ever, whilst three dimensional effects are becoming more commonplace.  Two dimensional graphics card applications are pushed to the limit with applications such as Photoshop and Illustrator, with the use of such programs increasing all the time effective graphics cards are essential.

Three dimensional graphics are typically used in video games.  Texture effects, particle effects and lighting all require heavy use of three dimensional shades and renderers in the video card.  Whilst some rendering takes place in the CPU of the computer, many of the work is devolved to processes within the video card memory itself.

A video card can come in various types.  Some older video card models may still use a PCI or Peripheral Component Interconnect port, but with speeds of computers doubling every few years, many use what is now regarded as an older port known as AGP, or Accelerated Graphics Port.  These types of video card are now considered basic and only really viable for the consumer if their motherboard only supports this type of connection.  PCI and AGP became a bottleneck for the speeds at which video card memory ran some five years ago, meaning that any video card utilising these connections won't be very efficient with newer three dimensional effects.  This type of video card may be useful for those with low three dimensional graphics requirements, however, as they will be able to render in 2D fast enough for the average user.

Now, most graphics card and video card types are available with a PCIe, or PCI Express connection.  This interface, now available on most motherboards across the range, allows for a much faster bus speed in the video card, meaning that information travels much faster across the system.  The amount of information travelling at any one time, the bandwidth, is big enough for the majority of video card types bought today.

However, even this connection has been pushed to one side by the most advanced video card manufacturing companies that quickly required two PCIe slots in order to get the most out of the video card.  PCI Express x 16 video card slots are now available to carry the immense amount of data that the most modern graphics card is available to generate.  Such a video card using PCIe x 16 slots will be geared towards the top end of video card owners, namely those playing games that utilise cutting edge technology.

Features

GeForce video cardConnecting a graphics card to a monitor used to be as simple as plugging a VGA cable between the graphics card output and the monitor.  However, video card types and LCD monitors have the benefit of digital signal transfer over old CRT monitors.  This means that the signal is degraded when using a VGA output to a monitor as it is transferred from digital to analogue and back.  Most modern video card types will offer S-Video output or DVI output, which is a direct digital video interface allowing the quality coming from the graphics card to hit the monitor undiminished.

It is also possible to link or daisy-chain graphics card or video card types together, with two in one system.  Nvidia, a popular video card manufacturer, calls this SLI or Scalable Link Interface, whilst ATi, their main competition, refers to this linking as CrossFire.  Both of these video card options normally require two compatible cards to work together at PCIe x 8.  However, extreme graphics engines call for extreme measures, and four card solutions are now available, working in a similar way to a dual-core CPU. Essentially, these are for the high end power users as these video card types can cost an awful lot of money.

Integrated graphics solutions are not necessarily available to purchase separately, but Asus produces a great deal of integrated video card types that come fitted to the computer.  These video card models are most often found in notebooks and laptops as well as some budget computers.  A while ago, these types of card were very much sneered at by the elite, but they have caught up quite significantly with the rest of the field and now offer reasonable performance.

Try to get a DirectX 10 or 11 compatible video card to ensure the computer is future proofed for the next five years or so.  Operating systems require newer graphics features in order to function correctly, so it is imperative to cater for these compatibility requirements when purchasing a new video card.

Graphics card types also occasionally have the ability to receive TV signals. These are known as TV tuner compatible cards and are becoming quite common with the advent of digital television.  Some will include Freeview built in, or similar.  Remember to pay your TV licence if you do own one of these cards if you use it to watch television, as this does unfortunately make you liable for the full TV license fee.

Size

Video card types come in all sorts of sizes.  The PCIe connection cards can be quite large in size and require a lot of space in the case of any computer.  The specialist two, three and four card setups are especially large and it is worth considering whether or not a new case will be required on top of the price of the card.

Aside from physical size, video RAM, or VRAM (with RAM standing for Random Access Memory) is very important in a video card these days.  VRAM is used as the space where the data produced by the video card is produced, and with bandwidth increasing all the time, it is necessary to get enough VRAM to ensure the card is fit for purpose.

Windows 8 and Mac OS X both require a significant amount of VRAM to output their various graphical nuances, whilst increasing screen resolution also requires VRAM.  As there are more pixels to push to the screen, so the VRAM requirement increases.  With many computer games running at 60 frames per second or more, video card types frequently come with between 256 MB of VRAM and 1 GB.  256 MB of VRAM should be more than sufficient for the average user for the next 5 years or so, but those looking to play complex games at a good frame rate should consider a video card with either 512 MB of VRAM or 1 GB.

As video games on the PC converge with their graphically inferior console ports, the graphical requirements for PC games has plateaued for a while, so a video card with 1 GB of VRAM should be more than enough for the foreseeable future.

Consider the budget available for a video card before purchase, as video card types are particularly scalable in type.  A mid-range video card will future proof any computer for the average home user for the next few years, whilst those looking to play games should be happy with a current medium to high end video card for a significant amount of time.  Those extreme power users looking for the ultimate performance in a graphics card will be able to get amazing graphics, but at considerable monetary cost.