Microsoft and IBM beat Intel and AMD in designing a CPU and GPU combo chip.
We've been waiting for the realization of all the talk about the combination of CPU and GPU into a single chip for some time now. AMD and Intel will be achieving that goal in the not too distant future, but a major software giant (along with some other hardware help) beat them to the punch.
Microsoft's latest redesign of the Xbox 360 houses a CPU and GPU combo chip, which includes IBM's triple-core design with ATI's graphics core, and is called Vejle, named after a city in Denmark (not Valhalla, as many previously believed).
The two parts originally debuted as 90nm parts (codenamed Xenon for the IBM CPU and Xenos for the ATI GPU) but are now married as one 45nm part produced by IBM and Globalfoundries.
Compared to the original duo of chips, this single SoC is 50 percent smaller in size and draws 60 percent less power. This clearly reduces cost for Microsoft in both silicon as well as design of cooling hardware.
Despite being the first of its kind on such a mass scale, the new Vejle chip contains only 372 million transistors, which is about half as many as the Core i5-760.
Despite the fact that the CPU still runs at 3.2GHz and the GPU at 500MHz, the overall design is capable of higher performance than the original design thanks to its integrated design. Sadly, instead of the new Xbox 360s being able to take advantage of the improvements, the system must be throttled to maintain compatibility with the previous designs.
Seen in the block diagram is the FSB replacement, which puts limits the latency and bandwidth on the new chip so that it'll behave the same way as the older chips.