AMD latest to tout GPU as stream processor


NVIDIA's G8800 presentation stressed that the company's overall approach to their new GPU product was that it's primarily a stream processor that can also be used as a GPU, and not just a GPU that can be used as a stream processor. I have to plead guilty to falling for the spin in my article on the architecture, but thankfully I was set straight via e-mail by someone who knows way more than me about this topic. There's plenty of dedicated, graphics-specific circuitry on the G8800—this thing was definitely designed from the ground up to push pixels, and it would be a lot slimmer if it didn't have to produce beautifully rendered 3D graphics. So from a hardware perspective, the G8800 is definitely a GPU with a unified shader model, but it has a shiny new stream-processing toolchain layered on top of it in addition to the existing graphics toolchain.

AMD was clearly watching the G8800 launch, and it probably reaffirmed their own plans to go ahead and play the "hey, it's not a mere GPU; it's a dedicated stream processor" with the launch of the AMD Stream Processor. The AMD Stream Processor is a repackaged ATI X1900 (R580) GPU with 1GB of GDDR3 DRAM on a standard PCIe daughtercard. In fact, it even looks like a typical graphics card, but it sells for a hefty $2,599.

AMD has been beta testing this hardware, and the related Close to Metal (CTM) initiative described below, for some time now. The card promises users 360GFLOPS of stream processing power.

In a lot of ways, this "is it mostly a stream processor, or is it just a GPU posing as a dedicated stream processor" discourse is just marketing-driven bunk. All modern GPUs are "stream processors" at their very core, but they have plenty of graphics-specific circuitry included in them that handles different parts of the rendering process. GPUs also come with an extensive toolchain to make graphics programming easier—a collection of APIs, languages, and other types of software abstraction that enable the programmer to use them specifically for rendering graphics.