What is a graphics card?
A Graphics Card is a piece of computer hardware that produces the image you see on a monitor.
The Graphics Card is responsible for rendering an image to your monitor, it does this by converting data into a signal your monitor can understand.
The better your graphics card the better, and smoother an image can be produced. This is naturally very important for gamers and video editors.
Types of graphics cards
Integrated – Graphics built into the motherboard where no add-in card is used. You’ll find these built into most ‘standard’ laptops and computers, they are a cost-effective model but cannot be easily upgraded.
Discrete – An add-in graphics card that is installed on to the motherboard as an extra component. Ideal for those wanting to modify their system by upgrading the graphics cards.
Most people using a modern computer for standard tasks like surfing the internet, creating documents or watching movies will be fine using the integrated graphics.
For users branching out into gaming or video editing, a discrete graphics card is usually needed to speed up the image processing time. Without this, the user may find their game lagging or jittering at crucial points.
GPU stands for Graphics Processing Unit. It’s the brain of the graphics card and is what creates the visuals you see on the screen. How powerful those GPU’s are will vary on the model you select.
The GPU works as a translator, it takes data coming from the CPU and transforms it into imagery. More complex visuals, like you find in high-definition games require more complex and quicker GPUs to accommodate the stream of data.
You can expand your PC internally by adding additional cards. Over the years graphics expansion slots have changed significantly from PCI (Peripheral Component Interconnect), AGP (Accelerated Graphics Port) to the latest PCI-E (Gen1/2/3) (PCI-Express) which offer the best bandwidth.
Some motherboards have expansion slots allowing users to add more than one graphics card, this is called SLI (NVIDIA) or CrossfireX (AMD) allowing users to get improved performance from their system. Users will need an SLI or Crossfire ready motherboard to use these technologies. The intention being to link two of the same graphics cards together.
SLI also known as Scalable Link Interface was developed by NVIDIA for linking multiple cards in a single system. SLI works by increasing the available processing power for graphics usage.
CrossfireX, also known as Crossfire, is developed by AMD.
Modern games provide 3D action and Photoshop realism, but for the user to get the best experience, their graphics card need to be up to scratch.
To get the crisp image, your PC must be able to deliver these details at an acceptable frame rate (this is the number of times a game can update/refresh the image you see). You’ll see this figure expressed as frames per second or FPS. If your graphics card frame rate is too low, the nice fluid motion you’d expect from your £50 game turns into a slow jerky crawl, no better than your PC from 1998.
Gaming and Editing
Graphics Cards are not just useful for gamers, discrete graphics cards can also significantly help users of photo and video editing programs as they will improve the speed in which images can be rendered as well as help users of high-def screens.
There are two main manufacturers of discrete graphics cards, AMD and Nvidia- Some users have allegiances to a particular brand but each will do the same job.
AMD also produce some integrated graphics option as well as the current market leader- Intel.
Current graphics cards also contain RAM memory, this is dedicated graphics memory, so it’s separate from your PC’s RAM. The capacity for most modern graphics cards will range from 512MB to 8GB with the most popular formats being DDR3 and GDDR5 SDRAM.
Memory is important on a graphics card as it allows users to play games at higher resolutions- Ideal for those using games like Skyrim, which contains very large texture packs.
A minimum of 1GB memory is recommended for gamers, but this needs to be balanced out with other aspects of the card and the resolution you play a game at.
Graphics cards can support multiple monitors, however the number is determined by the GPU and the number of outputs available. Check with the individual graphics card to find out how many monitors it supports.
Graphics cards can be connected to a monitor via a number of output options. You’ll need to buy a video card that matches a port on your monitor. Many video cards will have at least two or three ports with some supporting four or more.
VGA (Video Graphics Array) 15pin analogue connection also known as D-Sub- This is the earliest video connector and so is the least efficient. VGA ports work well enough but other ports provide a better video quality.
DVI (Digital Visual Interface) – DVI-I (carries analogue and digital signals) and DVI-D (Carries Digital signals only)- DVI tends to be found on most flat panel monitors, so is a useful link between card and screen.
HDMI – HDMI is one of the more popular connections due to its speed and versatility. HDMI will carry both video and audio signal.
DisplayPort –The connection is becoming much more popular, and will be been seen in the new generation of monitors. It can carry video, audio and other forms of data.
Form Factors (Size and Shape)
As with many components style and design of a graphics card can be important. If you happen to be short of room in your PC there are slim line options as well as full size components.
ATX/Full height – this is essentially the fully sized card/bracket for standard desktop without space issues.
Low Profile – half height graphics card slimmer than the ATX style and will accept a smaller bracket often used in HTPC