Dual Core Architecture

First of all what is dual core? What do we mean by dual core or multi-core processor?

We have two or more execution cores in the same processor package. So, on the lefthand side is the representation of the Pentium D processor, dual core processor based on the 90nm technology, with two independent execution cores, each with its own L2 cache. The picture shows that they are one piece of silicon, one monolithic piece of silicon with two dies mapping together. The mask is laid out, and when the wafer goes to the factory you can see that the two dies that are next to each other will be cut out as one piece of silicon and placed in the package.

The 65nm process will be used for multi-chip processors and instead of the two individual cores physically connected with silicon, there will be two independent pieces of silicon. They will be able to select those from anywhere on the wafer, even across wafers. But the selected two pieces of silicon should be of the same speed, to be put in the package.

When you have a chip in your hand you will not be able to identify by looking at it, whether it is a single piece of silicon or two pieces of silicon: electrically and physically it looks the same. But if you X-ray it, you will clearly see what?s in there. But whether it is one or two pieces of silicon it doesn?t actually matter: it makes no difference to the OEM or the end user.

The single piece of silicon or two pieces of silicon design choice depends on Intel?s design efficiency and manufacturing efficiencies and you will see this change over time.