Besides the central processing unit (CPU), the graphics processing unit (GPU) has the biggest impact on your computer's performance. The graphics card translates the information your computer is working on into images and sends them to your screen. The more powerful the GPU, the faster information can be displayed and the better the overall visual experience will be.

In the early days of PCs, the CPU was responsible for translating information into images managed in special areas of memory called "frame buffers" and then painting those images on displays. General purpose CPUs are not very fast at performing this type of process, so "graphics accelerators" were created to speed things up. This has become even more important the more popular graphical user interfaces (GUIs) such as Windows have become.

Today's GPUs are very good at processing large amounts of graphical information and performing parallel tasks, making them incredibly fast, not only for displaying text and graphics in windowed GUIs, but also for processing 3D graphics in today's advanced video games. GPUs can also efficiently perform other processes where a lot of data needs to be manipulated in parallel.

Read our guide below to learn more about choosing the right graphics card for you.

Why is your graphics card important?

For most people, playing games is the most graphics-intensive task you'll have to perform on your computer. So it's no wonder that serious gamers spend hours researching the latest GPU technology and often upgrade their GPUs regularly. As GPUs get faster and faster, games are written to take advantage of the extra speed, which drives manufacturers to create even faster GPUs.

If you're not a gamer, the capabilities of your graphics card may not be as important to you unless you're using other types of applications that can directly benefit from the special processing capabilities of the graphics card. Examples include video editing, where the GPU can be used to speed up processes such as video encoding, and computer-aided design/manufacturing (CAD/CAM) applications such as AutoCAD, which can also use the GPU to significantly increase performance.

Choosing a GPU is therefore an important part of building, buying or upgrading a PC. As with any PC component, the first question to ask when choosing a graphics card is how will you use them?

Gaming

The gaming industry has driven GPU technology faster and further than any other group. Today's PC games are more realistic and complex than ever before, and the increasing performance of modern GPUs is both part of the reason and a response to gamers' demand for better-looking games.

Simply put, if you're building a gaming PC, the GPU is your most important acquisition. Other components can make a difference in performance, such as CPU and RAM, but getting a GPU that is too weak for your chosen games is bound to be disappointing.

However, there are different types of games and not all of them require the most powerful GPU on the market. Therefore, it is important to read the required, recommended and optimal specifications of the game to make sure that you get the right GPU. Buying the best GPU you can afford is a great way to future-proof your build and keep it ready to play popular games that have yet to be released.

Video and professional applications

Another demanding group of users are those who perform complex tasks such as 3D rendering and video editing. High-end applications such as AutoCAD and Adobe Premiere Pro can use GPUs to accelerate processing and enable faster and more efficient workflows.

In fact, there is a class of GPUs that are designed specifically for these users. These workstation GPUs are optimized for these applications, and their drivers are certified to be stable and reliable. These GPUs are not always the best at running games, although they can be significantly more expensive than consumer GPUs.

In this guide, we'll focus on more mainstream graphics cards. If you need a GPU for professional applications, you'll likely be looking for the best options outside of the normal GPU market.

Is it definitely worth it?

If you don't play games or run creative applications that may use the GPU for acceleration, you may not need to invest as much money in your graphics card. If your primary job is running productivity applications, web browsing, email management, and other typical low-end PC tasks, you'll want to spend more time choosing the right RAM, CPU, and memory.

Integrated vs. discrete GPUs

Some processors have integrated graphics, that is, GPUs that are built into the same component as the CPU itself or are otherwise tightly coupled to the CPU. These embedded graphics components are typically low-performance options that provide enough power for the operating system and running web browsers, email clients, productivity applications, and other routine programs, but no more than enough for casual gaming.

This guide is about discrete graphics cards. Individual GPUs range from relatively inexpensive entry-level options to extremely powerful GPUs that can cost well over $1,000 on their own. You can buy discrete GPUs as part of off-the-shelf systems, for your home PC to upgrade an older GPU, or even in a laptop.

Mobility vs. desktop

Choosing a GPU isn't just important if you're building or buying a new desktop computer. Mobile computers also use GPUs, and if you want to game on the go, you should consider whether your portable system only has a built-in GPU built into the CPU or whether it has a discrete GPU.

There was a time when mobile GPUs were something completely different from their desktop counterparts. The good news for mobile gamers is that today's gaming notebooks use discrete GPUs that are very close in performance to their desktop counterparts or are optimized to fit impressive performance into very thin and light notebooks.

Ray tracing: the latest advances in realistic graphics

Since we originally developed this guide, a new technology has hit the streets that promises to dramatically improve the quality of graphics in games. The technology, known as "ray tracing," enables more realistic lighting effects through techniques that essentially simulate the behavior of light. As Nvidia puts it:

"Ray tracing calculates pixel color by tracking the path that light would take from the viewer's eye through a virtual 3D scene. As light passes through the scene, it can bounce from one object to another (causing reflections), be blocked by objects (causing shadows), or pass through transparent or translucent objects (causing refractions). All of these interactions are combined to create the final pixel color, which is then displayed on the screen.