Intel’s Ivy Bridge series of processors were designed from the outset to be split apart and recombined to create variants of the base platform, Intel architecture project manager Brad Heaney explained during the Wednesday keynote session at DAC 2012.
Ivy Bridge was “made for quick chops”, Heaney noted. “We didn’t want to do four chips one by one. We wanted to do one and then derive the others from it.”
The individual Ivy Bridge derivatives were distinguished primarily by the number of x86 processor cores and the graphics engines. The primary design was the 4+2 configuration, Heaney explained: four processor cores and a double-sized graphics engine. From that, two processor cores were removed and the floorplan adjusted to minimise overall area to create a 2+2 configuration. Replacing the graphics engine with a smaller, lower-cost version led to the 4+1 and a 2+1.
“These can be taped out back to back by preplanning how they are derived from each other. It is a key part of our productivity,” said Heaney.
Artour Levin, who managed overall chip integration, said during the later Q&A session: “The four different dies were produced within days of each other.”