The graphics card: the great unknown

A key component of any computer, the graphics card plays an essential role in how any PC works. Critically important, this component ensures all graphical information is displayed on your monitor. Its job is to process graphical data to deliver an acceptable visual output for the user.

Definition and purpose

The graphics card is connected to the screen (using a VGA, DVI, USB or HDMI connector). Its main function is to reduce the workload on your computer’s processor.

More precisely, this component handles the processing of graphical data in order to make use of:

• Operating system features
• Video editing or image editing software
• Launching a video game (which requires a powerful graphics card)

A quick tip: remember to regularly update your graphics card drivers to avoid issues such as:

• Screen flickering
• Frozen images
• Black screens
• BSOD (Blue Screen Of Death)

A graphics card is effectively a small computer inside your PC. It has its own processor, its own RAM and even its own cooling system (fans).

Depending on its power, a graphics card can output images at high resolutions (8K, 4K, 1080p, 720p). So if you want top image quality, choose a powerful card.

Key criteria when choosing a graphics card

On the market, several manufacturers offer graphics cards (AMD, NVIDIA, INTEL). With such a wide range available, it can be hard to decide, so here are some key criteria to focus on:

• How you plan to use the graphics card: office work, multimedia, gaming, or professional workloads (accounting, CAD, architecture software, etc.).
• The physical size of the graphics card, which must match your PC case
• The budget you are prepared to invest
• Power consumption, generally expressed in Watts
• Available memory and supported frequency
• Compatible cables: VGA for connecting to a monitor, S-Video for a TV or projector, HDMI for connecting HD displays, DVI for monitors and TVs, DisplayPort, etc.

The graphics card connects to the motherboard via the PCI EXPRESS slot. This allows the main processor to communicate freely with the components on the graphics card.

• The graphics processor or GPU: this is the processing unit that handles graphical data.
• RT cores (only on Nvidia): these are small processors dedicated to Ray Tracing calculations (a graphics technique that improves shadows and lighting in rendered scenes).
• Video memory or VRAM: this manages image data. It handles the processing of system information and display output. The latest models can reach 24GB of VRAM.
• The BIOS: this is a program stored in ROM, containing all the data needed for the graphics card to start up.

Types of graphics cards

Chip manufacturers (AMD, NVIDIA, INTEL) and brands (ASUS, EVGA…)

To get the best performance, your choice needs to be as informed as possible. There are real differences between graphics cards depending on the chip manufacturer. The most common GPU manufacturers are AMD and Nvidia. However, they do not usually sell the cards directly. They mainly design the chip architecture and make their technology available to board partners such as:

• Asus,
• Gigabyte,
• EVGA,
• KFA2
• …

These brands then optimise settings such as clock speeds, add more memory and design custom cooling solutions. The main differences therefore come down to the balance between performance and price. Longevity is influenced by clock speeds, onboard memory and the cooling system.

• With NVIDIA: graphics card generations are identified by the hundreds digit in the model number. For example, a GeForce GTX 7XX series card is from 2017. Then you have the GeForce 9XX series from 2015. In 2018, the GeForce RTX 20XX series arrived. More recently, the “green team” released the 3000 series, which is extremely powerful (capable of running games in 4K).

One series is separate: the GeForce TITAN range. These are considered the ultimate graphics cards. The latest model in this line is the NVIDIA RTX TITAN. Nvidia also offers cards dedicated to specific professional tasks. These include the Tesla, Quadro and Maximus ranges.

• With AMD: you will find the same concept of generations as with NVIDIA. The graphics cards follow this rough chronological order: Radeon Rx300 for 2014, Rx400 for 2015 and Rx500 for 2016. In 2017, however, the manufacturer introduced a new architecture and decided to give it a new name: Radeon Rx Vega.

Graphics card ranges and generations

Generally speaking, the more recent the graphics card, the better its performance. As a rule of thumb, each new generation brings around a 20% improvement.

Another way to distinguish graphics cards is by range or tier. For Nvidia, the higher the number in the model reference, the higher-end the card. For example, a GeForce RTX 3060 is less powerful than a GeForce RTX 3080 or RTX 3090.

For AMD, the principle is similar. A Radeon RX550 is an entry-level model compared with a Radeon RX580. More recently, the naming scheme has changed and we now see RX 6XXXX, with or without the XT suffix.

A GPU runs at a speed measured in Megahertz, which is the unit used to indicate how fast it can process data. This allows you to compare graphics cards within the same range. The higher the clock speed, the higher the number of frames per second.

Memory size also differentiates graphics cards. This component is used to store high‑resolution textures and add certain effects when needed. The aim is to make video games sharper and better looking. At the moment, gaming graphics cards typically offer between 8GB and 11GB of memory. For cooling, some cards are fitted with dual or even triple fans for greater durability and better performance.

IGP or integrated graphics processor

Some processors include a small integrated GPU (INTEL, AMD). These work in the same way as dedicated graphics cards, but the difference lies in their power. They are not powerful enough to run the latest AAA games. Their use is mainly limited to office tasks, media playback and web browsing.

Installing a graphics card

A high‑performance graphics card that is poorly installed will not work properly. Here are some tips to help you install it correctly:

• Remove any protective stickers from the card and from the fans
• Use a paper towel lightly dampened with alcohol to remove any marks
• Plug the graphics card into one of the PCI Express 16x slots on the motherboard. If there are several slots, choose the top one
• Remove any I/O slot covers from the case. Secure the card to the case using the brackets and tighten the screws so the card sits straight and firmly in place.
• Connect the graphics card to the PC’s power supply (6‑pin, 8‑pin, 2×8‑pin, etc.).
• Connect the cable linking the graphics card to the monitor
• Check that the computer detects the graphics card (via your OS)
• Then install the drivers, which you can download for free from the manufacturers’ websites.
• Run a few tests, particularly using benchmark software, to check the health of the graphics card (performance, temperature, etc.).