The 45nm processor integrates two 65nm chips on the previous Xbox 360. These were an IBM processor with three 3.2 GHz Power PC cores and an AMD graphics chip using 48 unified parallel shaders. The new set up integrated an IBM embedded DRAM die.
But the interesting thing is that when the pair came to design the chip they didn’t need to create any new logic blocks. In fact the whole design thing could be done on the cheap thanks to the way the chips had been designed in the first place.
Big Blue updated the chip’s front-side bus but most of the design work was focused on ways to bring the separate blocks into an optimised and unified 45nm IBM silicon-on-insulator process.
The integrated chip is a smaller, cooler processor that has a smaller motherboard and simpler power supply. It only needs one heat sink and a relatively low-speed, quiet fan.
Microsoft said that the process has reduced power consumption by 60 percent and cut die size in half. Talking at Hot Chips the two companies looked like they would be working together on a number of similar projects.