One of the Windows 7 features many aren’t aware of is how the new OS can use the Graphics Processing Unit (GPU, or simple video cards / subsystems) to do other work than video display, speeding up the user experience.

Windows 7 includes GPGPU / DirectX 11 / the Direct Computing API

I’m more grounded in Windows than I am in OS X, so again I will highlight that, though I’m agnostic when it comes to getting the work done . . .

AMD’s ATI division supports this work via several new cards that directly support DirectX 11 via their “Stream” technology, and Nvidia supports this with their current DX10 / 10.1 cards via CUDA; Nvidia also will continue to support this in upcoming DX11 cards. Both manufacturers have quality drivers (32 and 64 bit mode) for Windows 7; I am just using the default Microsoft WHQL drivers, and have had no issues.

DirectCompute is essentially Microsoft’s answer to Khronos’ OpenCL for Windows. It is intended to be used in games and other consumer software to speed up multimedia algorithms via the considerable computational prowess of on-board GPUs. This leaves the CPU free to do other tasks, or just to increase the number of effective cores / CPU’s that you are throwing against that 1080p movie rendering project.

These days even non-business users want to speed up everything they can in their computing worlds; since most applications do not even activate the hugely powerful 3D  engine of the two most common higher-end GPU makers, there’s a lot of room here to significantly increase system functionality.

One of the many manufacturers lists the following benefits for Windows 7 with their cards :

DirectX Compute: The most significant addition to Windows 7 is the DirectX Compute API for GPU-accelerated compute applications. This API will enable great visual and interactive experiences such as new high-quality video and photo enhancements, simplified ways to interact with your devices, faster, more responsive PCs, and even new realistic gaming effects. One example is a cool new drag and drop feature built directly into Window 7. This feature allows quick and easy copy and conversion of media files from your PC directly to your portable media player. With GPU-acceleration built-in, you can perform this conversion up to 5X faster, so that you spend less time waiting and more time enjoying your movie. DirectX Compute runs on NVIDIA’s 100Mu+ CUDA-enabled GPUs. For a truly Premium Experience for Windows 7 equip your PC with an EVGA GeForce® DirectX 10 GPU with built-in NVIDIA CUDA technology.

DirectX Video Acceleration –High Definition (DXVA-HD): Windows 7 expands the use of the GPU to accelerate video playback and offer a better overall experience for watching high-definition H.264/MPEG-4 video content. DXVA-HD uses the GPU to improve video decode, processing, and presentation. This new hardware-accelerated engine is particularly helpful when dealing with the interactive features of Blu-ray material including the compositing of Picture-in-Picture with fullscreen graphics, a task that is extremely taxing when performed on the CPU.

Direct2D: Aligned to the end-consumer desire for basic applications to be more visually compelling, Microsoft introduced a new 2D API to Windows 7. Direct2D uses the advanced processing power of the GPU to provide hardware acceleration for 2D geometry, bitmaps, and text. Using Direct2D, applications will be able to achieve higher visual quality and better responsiveness.

DirectWrite: Building on the capabilities of Direct2D, DirectWrite offers hardware accelerated fonts, complete with antialiasing for unrivaled visual quality. This API will translate to the best reading experiences ever on a PC.

Microsoft has also made significant changes to the 3D Aero Windows desktop in Windows 7. With the new Windows Display Driver Model (WDDM) v1.1 built for Windows 7, the Windows desktop is able to leverage the DirectX 10 API to provide a higher-performance experience. In addition, Windows 7 effectively takes advantage of the GPU to reduce by half the amount of memory consumed to draw desktop windows. The result is better windows responsiveness and more system memory available for other applications.

When similar OpenCL support arrived from Apple (when they introduced Snow Leopard / OS X 10.6), you can bet this trend isn’t going away anytime soon. Again, both ATI and Nvidia support OpenCL.

Further references :

http://windowsteamblog.com/blogs/partner/archive/2009/08/22/gpu-computing-and-windows-7.aspx

http://www.microsoft.com/video/en/us/details/9d6d9ca5-3668-4e46-b038-107535de0be7

http://blogs.pcmag.com/miller/2009/10/windows_7_and_gpu_computing_a.php

http://www.extremetech.com/article2/0,2845,2354336,00.asp

http://www.geeks3d.com/forums/index.php/topic,681.0.html

http://www.ditii.com/2009/08/22/gpu-computing-via-directcompute-in-windows-7/

http://www.hpcwire.com/blogs/A-Pervasive-GPU-Computing-Strategy-65667732.html

http://www.evga.com/articles/00511/