8/25/2010 8:31 AM
By Jon Stokes
At Hot Chips today, Microsoft's Xbox team unveiled details of the system-on-a-chip (SoC) that powers the newer, slimmer Xbox 360 250GB model. Produced on the IBM/GlobalFoundries 45nm process, it's fair to say that the new SoC (pictured above) is the first mass-market, desktop-class processor to combine a CPU, GPU, memory, and I/O logic onto a single piece of silicon. The goal of the consolidation was, of course, to lower the cost of making the console by reducing the number of different chips needed for the system, shrinking the motherboard, and reducing the number of expensive fans and heatsinks.
The SoC also makes the new Xbox design more power efficient, which is nice for consumers, but the real motivation behind boosting the console's efficiency is to reduce the size and cost of the power supply unit, and to realize the aforementioned savings on cooling apparatus.
Microsoft engineers presented the new SoC and apparently did a lot of the layout (or perhaps all of it) themselves. Given the unique requirement of consoles—the system must perform exactly like the original Xbox 360—and despite a five-year gap and multiple iterations of Moore's Law, the consolidation presented a few interesting challenges.
Read more (including a larger version of the block diagram) here.