What are the characteristics that define a modern CPU? It is not sheer power any more? A Pentium D 805 dual core is still a power hog, even if it can run at 4.1 GHz and is truly smokin' with an utterly monstrous clock rate. More important is power consumption: Intel wants to stay within the 130-W power envelope with the quadruple Core 2 Quadro processor. The 130-W figure was almost achieved by the Pentium Extreme Edition 965 and the Core 2 Quadro processor does it again; but it packs a total of four CPU cores on the chip now.

The four cores are not located on a single piece of silicon, but the two Core 2 chips are placed next to each other inside the processor package. Consequently, the transistor count doubles to an impressive 582 million.

We had to do the math as well: More than two Core 2 "Conroe" units do not fit in the existing LGA 775 casing, as the surface is simply not large enough. With a surface area of 143 mm2 per Core 2 dual core, at least 572 mm2 would be required to fit four units (a maximum of 625 mm2 is available). The chips' elongated shape (10.48 mm x 13.63 mm), however, prevents four of them from being accommodated. It is thus safe to say that Intel has reached its limit with dual dies and four cores with 65-nm production. A slimmed-down version with 2 MB temporary storage each would make four chips feasible, but then the maximum power dissipation of over 200 W would no longer be economically justifiable. We are confident that the next step will be to get four processors on a single die with shared L2 cache.

But that is just the beginning. The conversion to 45-nanometer production technology is slated for mid-2007, and starting in 2009, thanks to EUV lithography, Intel plans to manufacture 32-nanometer devices, at which point - if everything works as envisioned - the company could have a two-year technology edge over most other chipmakers.

The Quad Core CPU In Detail

Intel Core 2 Quadro with 2.66 GHz and a total of 8 MB L2 cache. Four processing units are packed inside a single CPU package.

Rumor has it that Intel will launch the fastest Quad Core processor as Core 2 Extreme.

On the left the Core 2 Duo and on the right the Core 2 Quadro.

The back of both processors reveals some differences.

A look at the physical layout of the two CPU cores with two processors each.