EMZETT.Graphics Cards
In short: Expansion cards with their own processor (GPU) and memory, specialised in the parallel computation of image content — central for gaming, video editing and increasingly AI training too.
In more detail: While a CPU has a few, very versatile cores, a GPU has thousands of simpler cores, optimised for massively parallel tasks (e.g. computing every pixel of an image at once). The card is connected via PCIe and connected to the monitor via HDMI/DisplayPort.
In Depth
CPU vs. GPU: different kinds of parallelism
The basic architectural difference between the CPU and the graphics card (GPU) explains why both exist side by side: a CPU has few, but extremely versatile cores, optimised for complex, sequential decision logic. A GPU, by contrast, has thousands of simpler cores that individually can do less, but apply the same operation massively in parallel to huge amounts of data at once — exactly the pattern that occurs when rendering images, where, for example, millions of pixels can be computed independently of each other. This principle of parallelism also makes GPUs excellently suited for AI training and scientific computations that can be broken down into many similar subtasks.
VRAM as dedicated memory
Besides the actual graphics chip, a dedicated graphics card has its own, very fast video memory (VRAM) that works independently of the system’s RAM — its capacity limits how high-resolution textures can be and how much graphics data can be processed at once before data has to be reloaded more slowly. VRAM is optimised for particularly high bandwidth (not necessarily the lowest latency), since huge, contiguous amounts of data (textures, frame buffers) often have to be transferred during rendering.
Integrated vs. dedicated graphics
A distinction is also made between integrated graphics (built directly into the CPU, uses the normal system RAM, saves cost and power, but limited in performance) and dedicated graphics cards (their own expansion card with its own memory, considerably more powerful, but more expensive and power-hungry) — for demanding gaming or professional graphics work, there’s usually no way around a dedicated card, while integrated graphics is usually completely sufficient for office work, video playback and simple applications.
Cooling and power consumption
Powerful graphics cards are often among the most power-hungry individual components in a PC — high-end models can draw several hundred watts, considerably more than a typical CPU. This requires correspondingly sized power supplies and powerful cooling systems (often with several large fans directly on the card), since the resulting waste heat can’t otherwise be reliably dissipated.
See also: PCIe, HDMI, DP (DisplayPort), CPU, RAM