Ever since Intel showed off its 80-core prototype processor, people have asked "Why 80 cores?"
There's actually nothing magic about the number, according to Jerry Bautista, co-director of the Tera-scale Computing Research Program at Intel, and others. Intel wanted to make a chip that could perform 1 trillion floating-point operations per second, known as a teraflop. And 80 cores did the trick. The chip does not contain x86 processing cores, the kind of cores inside Intel's PC chips, but cores optimized for floating-point (or decimal) math.
Other sources at the company pointed out that 80 cores also allowed Intel to maximize the room inside the reticle, the mask employed to direct light from a lithography machine to a photo-resistant silicon wafer. Light shining through the reticle creates a pattern on the wafer and the pattern then serves as a blueprint for the circuits of a chip. More cores, and Intel would have needed a larger reticle.
Intel is now trying to take what it learned with the 80-core prototype and make commercially available chips. Read more here.