Graphics processing unit (GPU) - a separate device of a personal computer or game console, which performs graphics rendering; in the early 2000s, graphics processors began to be massively used in other devices: tablets, embedded systems, digital TVs.
Modern graphics processors process and display computer graphics very efficiently, thanks to a specialized pipeline architecture they are much more efficient in processing graphic information than a typical central processing unit.
The graphics processor in modern video adapters is used as a 3D graphics gas pedal.
It can be used as part of a discrete graphics card, as well as integrated solutions (integrated into the north bridge or a hybrid processor).
Distinctive features in comparison with the CPU are:
architecture that maximizes the speed of texture calculation and complex graphics objects;
a limited set of commands.
The high computing power of GPUs is explained by the peculiarities of the architecture. Modern CPUs have a small number of cores (as compared to graphical processors), while the graphical processor was originally designed as a multi-threaded structure with many cores. The difference in architecture also results in a difference in principles of operation. While CPU architecture assumes a sequential processing of information, GPU was historically designed for computer graphics processing, so it is designed for massively parallel computing.
Each of these two architectures has its own merits. The CPU performs better with sequential tasks. With a large amount of information to be processed, the GPU has a clear advantage. There is only one condition - parallelism must be observed in the task.
External graphics processor (eGPU)
An external graphics processor is a graphics processor located outside the computer case. External graphics processors are sometimes used in conjunction with laptop computers. Laptops may have a large amount of random access memory (RAM) and a sufficiently powerful central processing unit (CPU), but are often lacking a powerful graphics processor, instead using a less powerful but more energy-efficient integrated graphics chip. Built-in graphics chips are usually not powerful enough to play the latest games or for other graphics-intensive tasks such as video editing.
Therefore, it is desirable to be able to connect the graphics processor to some external notebook bus. PCI Express is the only bus commonly used for this purpose. The port can be, for example, an ExpressCard or mPCIe port (PCIe × 1, up to 5 or 2.5 Gbps respectively) or a Thunderbolt 1, 2 or 3 port (PCIe × 4, up to 10, 20 or 40 Gbps respectively). These ports are only available on some laptops.
External GPUs have not had much official vendor support. However, this has not stopped enthusiasts from adopting eGPU settings.
At the software level, a video processor for its organization of calculations (3D graphics calculations) uses some kind of application programming interface (API).
The earliest gas pedals used Glide - API for 3D graphics, developed by 3dfx Interactive for video cards based on their own graphics processors Voodoo Graphics.
Generations of gas pedals in video cards can be counted by the versions of DirectX and OpenGL they support.