Used primarily for 3-D applications, a graphics processing unit is a single-chip processor that creates lighting effects and transforms objects every time a 3D scene is redrawn. These are mathematically-intensive tasks, which otherwise, would put quite a strain on the CPU. Lifting this burden from the CPU frees up cycles that can be used for other jobs.
The first company to develop the GPU is NVIDIA Inc. Its GeForce 256 GPU is capable of billions of calculations per second, can process a minimum of 10 million polygons per second, and has over 22 million transistors, compared to the 9 million found on the Pentium III. Its workstation version called the Quadro, designed for CAD applications, can process over 200 billion operations a second and deliver up to 17 million triangles per second.
The GeForce NVIDIA GPU card is compatible with the following graphics APIs : OpenGL and Microsoft's DirectX, Intel's Accelerated Graphics Port (AGP) technology and AMD 's 3DNow!
The Quadro is an OpenGL specific card with driver support for Pentium III Xeon and AMD Athlon CPUs.