Smithfield Processor Core
If we analyze the potential of Intel’s today’s processor cores the picture will not look very optimistic. Right now Intel has very limited opportunities for further performance increase by raising the clock frequencies. And even though the company sticks to the official position claiming that the users do not need any further performance growth and care more about processor functionality, you will hardly be satisfied with just this functionality. Especially since Intel’s main competitor, AMD, managed to get significantly ahead of Intel at least in terms of gaming performance of its top processors, and the games are known to be among the major “consumers” of hardware resources.
Unfortunately, the Prescott and Prescott-2M processor cores Intel has at its disposal today, cannot boast any significant frequency potential limited by the 4GHz rate. Right now Intel has almost completely exhausted this reserve.
So, Intel engineers simply have to resort to some alternative measures in order to improve their processors performance, such as release of CPUs with dual-core architecture.
In fact, Intel’s plans concerning the wide-spreading of dual-core architecture are remarkably overwhelming. Intel is claiming that the dual-core processors share among the desktop solutions will reach 70% by the end of 2006. So, you see clearly how big the company’s bet on the dual-core solutions actually is.
The first dual-core Intel processors to come into the market will be designed for the desktop segment and will be also known under the codename Smithfield. Since there are no other desktop processor cores besides Prescott and its modifications, this was exactly the core they used to design Smithfield. So, the new dual-core Intel processors turn out not so new in the long run, as they inherit most their features from the Pentium 4 processors already available in the market.
In fact, Smithfield processor core used as a basis for Intel’s first desktop dual-core CPUs is a concatenation of two Prescott revision E0 cores designed on a single semi-conductor die. The same die also carries an arbiter responsible for sharing the processor bus between the cores. In other words, the two physical cores inside Smithfield communicate only on the system bus level.
As a result of this design, the die size of the Smithfield core turned twice as big as the Prescott die. Intel’s dual-core processors feature 230 million transistors located on a 206sq.mm die.
Note that since Smithfield is practically designed as a combination of two Prescott dies, its L2 cache is 2MB big. However, this cache memory is split half and half between the two cores so that each of them uses its own 1MB L2 cache.
There is one more important consequence resulting from this block-type Smithfield construction. Smithfield inherited from Prescott the entire list of technologies including 64-bit EM64T extensions support, Execute Disable Bit technology, and the entire range of Demand Based Switching options for power consumption and heat dissipation management including C1E, TM2 and EIST technologies.
However, I have to draw your attention to the fact that unfortunately, the cores in the dual-core processor cannot work at the same frequency as they would if used in a single-core design. The primary reason for that is the limitations imposed by the heat and power requirements, since the two cores combined within the same die lead to a significant growth of these two parameters. Therefore, dual-core Smithfield processors work at much lower clock frequency than their “forefathers” – CPUs on Prescott core.