Beyond Computing » GPU

GPU  

GPU - Graphics Processing Unit

These are chips that very efficiently manipulate and show computer graphics, and thanks to their extraordinary structure, they are more efficent from CPUs (Central Processig Units) when are questioned komplex graphics algorithms.

GPU implements numberous simple graphics operations with a way that is possible to execute them much faster then CPU could do. The most basic operation of first 2D oriented graphics cards included BitBLT (Bit Block Transfer), it is acctualy operation that combine 2 images into 1, then operations of drawing of square, triangles, arcs and circles. Modern graphics processors have implemented support for 3D computer graphics. At the beggining they were used for acceleration of intenzive memory requests, like mapping of textures and rendering polygons, later there were added elements that speedup geomethric calcucations like replacing lines into other coordinate systems. Latest improvements on graphics processors includes support for programmabile shaders that can manipulate with lines and textures with many, same operations that CPU supports, like various interpolation techniques that are used for enchancing picture quality.

Graphics processors produced after 1995 support "YUV color space" (today YUV presents the most used system of colors in TV reproduction which is used on PAL and NTSC systems, and its based on better luminance of colors unlike RGB, which YUV was based on (the one that is mostly used in computer graphics) like hardware attachment that is very importante for reproduction of digital video. Meny graphics processors produced after year 2000 support MPEG coding that allowes for better and more efficiant video compression. Newesr graphics cards even can decode video content in real-time by card itself, and with taht they reduce CPU use.

Typical, modern graphics card is connected with CPU and system memory over motherboard, and bus (PCI, AGP, PCI-E). Graphics processor has limmited access to amount of video mamory which is located directly on card, and gives support for lot larger speeds then dynamic RAM. Thats why price of these memories is bigger. Today graphics cards have about 256 MB, 512 MB, even 1 GB video memory, which is sometimes more than amount of system RAM.