Immediately after AMD and ATI consummated their 2006 merger, their first order of business was to announce plans and a timeframe for the first true offspring of their corporate union: a CPU/GPU fusion product called, aptly enough, "Fusion." This Fusion idea has taken more than one shape in AMD's roadmaps since it was first announced, and I won't summarize that history here, though it is worth recalling that AMD had been planning to use a newly developed processor core, codenamed "Bulldozer," for the CPU half of Fusion.

But in a financial analyst day meeting early this past December, AMD revealed that the company's first Fusion product would "use existing CPU core and GPU core technologies," suggesting that Bulldozer had gotten the boot in favor of a core from AMD's current lineup.

In a recent InfoWorld interview, AMD confirmed that Fusion will be a dual-core design based on the Phenom core in its initial incarnation. There's still no word on the GPU that AMD will pair with Phenom as the second core on the die, but apparently something will be announced relatively soon.

So now that we know that Fusion will combine a Phenom core with an as-yet unannounced GPU core, we can put together the following picture of AMD's mobile "Shrike" platform, due out in the second half of 2009.



AMD's "Shrike" Platform

Shrike is the successor of the Puma mobile platform that I described in an earlier article and that's set to launch sometime this year. At the heart of Shrike is the 45nm "Swift" processor; AMD is calling Swift an Accelerated Processing Unit (APU) because it contains both a CPU and a GPU. This "APU" (I'm not so sure this term is going to catch on) part should start sampling in late 2008 or early 2009.

In a nutshell, the Shrike platform simply moves the integrated graphics processor (IGP) off of the northbridge and onto the CPU die. In other words, the GPU core that AMD will integrate with Phenom will not be on the same level in terms of performance as a discrete GPU. This is more of an IGP with a significantly improved performance per watt ratio, which is why it will show up in laptops first.

Once AMD gets its feet wet with this initial, mobile-oriented design, it will begin to think about how to apply that same CPU/GPU concept in the workstation and high-performance computing (HPC) spaces. But truly leveraging a very tight level of integration between the CPU and GPU to do nongraphics work is more of a software problem than anything else, so the challenge for AMD and its partners lies first in finding an application domain to plug this into and second in adding enough value via acceleration to make Fusion (or its socket-level counterpart, Torrenza) a compelling reason to invest in AMD hardware.