Linchuan Chen

图形处理器（ Graphics Processing Unit ）， 是一种专门用来处理在个人电脑、工作站或游 戏机上图像运算工作的微处理器。 图形处理器使显卡减少了对中央处理器的依赖， 并分担了部分原本是由中央处理器所担当的工 作 Efficient at manipulating computer graphics highly parallel structure more effective than general purpose CPUs for processing of large blocks of data in parallel.

集成显卡 (Integrated GPUs)

独立显卡 (Discrete GPUs)

Intel (49.4%) Mainly integrated GPUs Nvidia (27.8%) The world's first 'GPU‘, GeForce 256, October 11, 1999 ATI (20.6%) acquired by AMD in 2006 Released its first Radeon 9700 GPU in 2002 Nvidia and ATI control 100% for Discrete GPU market.

In 90s, 2D GUIs were supported by graphic chips Early – Mid 90s, 3D Games Appeared 3D real time processing were CPU-assisted Low 3D Performance Leads to Hardware- accelerated 3D graphics. e.g. S3 ViRGE, ATI Rage,and Matrox Mystique. They are 2D GUI graphic chips with 3D features bolted on Microsoft provided strict one-to-one support of hardware for Direct3D. OpenGL is cross-platform The world first GPU (GeForce 256) supports hardware 3D processing

After 2000 GPUs allow users to do shading before displaying graphics to the screen Nvidia released the first shading capable chip GeForce 3 March 2001 ATI released Radeon 9700 in 2002, which supports shading with looping and floating point math operations

Stream Processing Stream: a set of data, similar to an image All input units are processed in a SIMD way This concept turns the modern GPU’s shader pipeline into general-purpose computing power General Purpose GPUs Especially benefits massive vector operations Can yield several orders of magnitude higher performance than a conventional CPU Because each GPU incorporates hundreds of shader cores

Nvidia GPUs CUDA SDK, OpenCL SDK Tesla Series GPUs Fermi Cards AMD (ATI) GPUs Use OpenCL Radeon Series

Integrates CPU and GPU on the Same Chip, and the GPU supports general purpose computation AMD Fusion (e.g. AMD A3850 APU) Intel Ivy Bridge Series (e.g. I7 3 rd gen) These are in fact a evolution of integrated graphic cards

Dealing with Highly Parallel Computations Ray Tracing, computational fluid dynamics, weather modeling, data mining. In the top 500 list, three of the top five fastest supercomputers in the world were CPU-GPU clusters However, GPUs are not good at handling branches or data retrieving. For tasks like MS word processing, CPUs are still the first choice