Rocking Team

Nehalem is the codename that indicates the new generation of Intel processors. The first Nehalem CPUs have the name of Core i7 and are destined to medium-high end desktop systems.

With these next few articles, we will be going through the architectural characteristics on these processors, so we can better analyze the performance results for these processors when compared to the Intel Core 2 Quad solutions currently in the market.

The importance of the Nehalem CPU is very high for Intel: it’s a completely new architecture, very different from what has been implemented by the company with the Core 2 family solutions. Intel follows a known approach with the Tick / tock terms. Each year, Intel presents a new generation of processors, that can either implement a completely new architecture, or be built using a more sophisticated technology.

Taking the Nehalem CPU’s as a reference, they can be inserted into what is called a “Tock” phase, which means a completely different microarchitecture generation from the previous ones. The same happened two years ago with the debut of the Meron family CPU, which later was called Core 2 Duo and Core 2 Quad, depending on the versions; in that case, the architectural change was done to replace the Pentium D CPUs.

The “Tick” phases indicate the uses of a new fabrication process: The Nehalem CPUs are built with 45nm technology, the same used on the Penryn family (Core 2 Duo and Core 2 Quad) currently available on the market. The “tick” phases also usually indicates an architectural restyling, with the implementation of some functions that are considered “minor”; for example, with the Penryn CPUs, besides the new fabrication process, there was also the introduction of SSE4 instructions that weren’t present on the Merom family.

The evolution to a 32nm process on the Nehalem CPUs is known by the name of Westmere; the processors belonging to this family will probably not be launched before the end of 2009, and also in this case with probably small innovations and enhancements, but without any changes on the architectures.

The choice of presenting their own solutions with this scheme comes from the fact that Intel has chosen to present new architectures by using a manufacturing technology that has been already launched, to avoid risking to end up with a CPU that doesn’t reach the expectations, instead of simply combining new architectures and new fabrication processes in the same line, which would be a lot more risky.