In the early days of computer video card or graphics card does not possess a processor. It has only a memory which is the main draw of the graphics card. The sizes of memory range from 1, 2, 4, 8, 16 and 32 MB for the high end type. That was then now memory capacity has expanded many more times the the smallest memory configuration for a graphics card is now set at 512 MB then from here the it can be 1 Gig, or more depending on your budget and requirements.
But as application grew in size and the task also required more details like rendering or 3D modelling or animation that could be mistaken for the real stuff. The memory may have more than it can handle. Manufacturer also needed to have a more active graphics card than what the current crop is offering. Somehow in application that require high output the processing task needs be taken from the CPU which traditionally handle all processing task. Enter the GPU or Graphics Processing Unit, now what is this exactly?
A graphics processing unit or GPU (also occasionally called visual processing unit or VPU) is a specialized electronic circuit designed to rapidly manipulate and alter memory in such a way so as to accelerate the building of images in a frame buffer intended for output to a display. GPUs are used in embedded systems, mobile phones, personal computers, workstations, and game consoles. Modern GPUs are very efficient at manipulating computer graphics, and their highly parallel structure makes them more effective than general-purpose CPUs for algorithms where processing of large blocks of data is done in parallel. In a personal computer, a GPU can be present on a video card, or it can be on the motherboard or -- in certain CPUs -- on the CPU die. More than 90% of new desktop and notebook computers have integrated GPUs, which are usually far less powerful than those on a dedicated video card.
The term was popularized by Nvidia in 1999, who marketed the GeForce 256 as "the world's first 'GPU', or Graphics Processing Unit, a single-chip processor with integrated transform, lighting, triangle setup/clipping, and rendering engines that is capable of processing a minimum of 10 million polygons per second". Rival ATI Technologies coined the term visual processing unit or VPU with the release of the Radeon 9700 in 2002.
As mention above this two company popularized the term GPU and VPU for marketing and branding purposes of both there respective product. Modern GPUs use most of their transistors to do calculations related to 3D computer graphics. They were initially used to accelerate the memory-intensive work of texture mapping and rendering polygons, later adding units to accelerate geometric calculations such as the rotation and translation of vertices into different coordinate systems.
Recent developments in GPUs include support for programmable shaders which can manipulate vertices and textures with many of the same operations supported by CPUs, oversampling and interpolation techniques to reduce aliasing, and very high-precision
color spaces. Because most of these computations involve matrix and vector operations, engineers and scientists have increasingly studied the use of GPUs for non-graphical calculations.
Dedicated graphics cards
The GPUs of the most powerful class typically interface with the motherboard by means of an expansion slot such as PCI Express (PCIe) or Accelerated Graphics Port (AGP) and can usually be replaced or upgraded with relative ease, assuming the motherboard is capable of supporting the upgrade. A few graphics cards still use Peripheral Component Interconnect (PCI) slots, but their bandwidth is so limited that they are generally used only when a PCIe or AGP slot is not available.
A dedicated GPU is not necessarily removable, nor does it necessarily interface with the motherboard in a standard fashion. The term "dedicated" refers to the fact that dedicated graphics cards have RAM that is dedicated to the card's use, not to the fact that most dedicated GPUs are removable. Dedicated GPUs for portable computers are most commonly interfaced through a non-standard and often proprietary slot due to size and weight constraints. Such ports may still be considered PCIe or AGP in terms of their logical host interface, even if they are not physically interchangeable with their counterparts.
Integrated graphics solutions
Integrated graphics solutions, shared graphics solutions, or Integrated graphics processors (IGP) utilize a portion of a computer's system RAM rather than dedicated graphics memory. They are integrated into the motherboard. Exceptions are AMD's IGPs that use dedicated sideport memory on certain motherboards, and APUs, where they are integrated with the CPU die. Computers with integrated graphics account for 90% of all PC shipments. These solutions are less costly to implement than dedicated graphics solutions, but tend to be less capable. Historically, integrated solutions were often considered unfit to play 3D games or run graphically intensive programs but could run less intensive programs such as Adobe Flash. Examples of such IGPs would be offerings from SiS and VIA circa 2004.
However, modern integrated graphics processors such as AMD's Fusion IGPs and Intel's HD Graphics are more than capable of handling 2D graphics from Adobe Flash or low stress 3D graphics, but struggle with the latest games like Battlefield 3. IGPs like the Intel's HD Graphics 3000 and AMD's Fusion IGPs have improved performance that may match cheap dedicated graphic cards, but still lag behind the more expensive dedicated graphics cards. While older platforms had the IGP integrated onto the motherboard, newer platforms (Intel Core i series and AMD Fusion) integrate the GPU right onto the CPU die.
Graphics Procession Unit will continue to be developed in all capabilities as more demanding high end application require more realistic and faster output.
