What is ATI Stream technology?
"ATI Stream is a set of advanced hardware and software technologies that enable AMD graphics processors, working in concert with the system’s central processor, to accelerate applications beyond just graphics", says AMD.
Put simply, it's software designed to utilise the raw parallel processing capability of a Radeon HD 4000-series graphics card, and put it to work on general computing tasks. Not dissimilar, then, to what NVIDIA's CUDA can do for its GeForce GPUs.
As we've stated before, modern graphics cards boast performance in excess of one trillion floating-point operations per second, and it makes implicit sense to have the GPU performing other duties when possible.
An obvious question remains, of course, and it's the same question we've been asking NVIDIA; just which general computing applications can harness all this extra power? NVIDIA has itself a useful partnership with Adobe, but other mainstream solutions remain few and far between.
The same holds true for AMD, who only goes as far as to state that ATI Stream-enabled software is currently in development from the likes of Adobe, ArcSoft, CyberLink and Microsoft. In development doesn't necessarily equate to coming soon, although, to AMD's credit, it's already working to make its ATI Stream SDK compliant with OpenCL. That transition, says AMD, will ensure easier development of Stream-enabled applications.
Importantly for consumers, OpenCL support for both AMD and NVIDIA GPUs should, in theory, result in GPU-accelerated applications that can harness the power of either GeForce or Radeon graphics cards.
At present, Stream-enabled applications are largely in development, so what's the use of Catalyst 8.12? Well, there is one Stream-enabled app that'll be available this month for consumers to see what GPU-acceleration has to offer. The application, AMD's own Avivo Video Converter, will be available as a freeware download and offers GPU-accelerated video transcoding.
In comparison, NVIDIA's similar transcoding software - Badaboom - retails at $30. AMD's freeware offering, we feel, could give it a quick initial boost in the GPGPU stakes, so let's see how the Avivo Video Converter performs.
For our benchmarks, we'll be putting ATI Stream to the test by comparing transcoding performance of AMD's Avivo Video Converter and VirtualDub. To get an idea of performance in multiple scenarios, we'll be testing with both a quad-core processor - Intel's Core 2 Extreme QX9770 with 12MB of L2 cache - and a dual-core processor - Intel's Core 2 Duo E8500 with 6MB of L2 cache. Each will be running on an MSI X48 Platinum motherboard with 4GB of Corsair XMS3 PC1066 memory, and we'll also be putting two GPUs to the test - a Radeon HD 4870 1GB and a Radeon HD 4670 512MB.
On to the results...
