Intel's Dual Core Strategy Investigated

Been hearing conflicting dual core information lately? Here's a compilation of everything we have and know about Intel's dual core plans for the next two years.

Dual Core for Desktops in 2005

Intel has yet to determine what brand they will market their first desktop chips under, although we'd expect them to continue to use the Pentium 4 brand but with some sort of appendage like Extreme Edition or Lots of Cores Version. Intel has, however, already determined what the specifications and the model numbers of their dual core chips will be.

Currently set for release in Q3 2005, Intel has three dual core chips on their desktop roadmap: the x20, x30 and x40. The only difference between these three chips is clock speed, with the x20 running at 2.8GHz, the x30 running at 3GHz and the x40 running at 3.2GHz. All of the chips are LGA-775 compatible and run off of an 800MHz FSB. Hyper-Threading is not enabled with Intel's dual core chips.

As far as architecture goes, the x-series of dual core CPUs from Intel are built on the little talked-about Smithfield core. While many have speculated that Smithfield may be Banias or Dothan based, it's now clear that Smithfield is little more than two 90nm Prescott cores built on the same die. There is a requirement for a very small amount of arbitration logic that will balance bus transactions between the two CPUs, but for the most part Smithfield is basically two Prescotts.

But doesn't Prescott run too hot already? How could Intel possibly build their first dual core chip out of the 90nm beast that is Prescott? The issue with Prescott hitting higher clock speeds ends up being thermal density - too many transistors, generating too much heat, in too small of a space. Intel's automated layout tools do help reduce this burden a bit, but what's important is that the thermal density of Smithfield is no worse than Prescott. If you take two Prescotts and place them side by side, the areas of the die with the greatest thermal density will still be the same, there will simply be twice as many of them. So overall power consumption will obviously be increased by a factor of two and there will be much more heat dissipated, but the thermal density of Smithfield will remain the same as Prescott.

In order to deal with the fact that Smithfield needs to be able to run with conventional cooling, Intel dropped the clock speed of Smithfield down to the 2.8 - 3.2GHz range, from the fastest 3.8GHz Prescott that will be out at the time. The reducing in clock speed will make sure that temperatures and power consumption is more reasonable for Smithfield.

Smithfield will also feature EM64T (Intel's version of AMD's x86-64 extensions), EIST (Enhanced Intel SpeedStep Technology) and Intel's XD bit support. Chipset support for Smithfield will come from Glenwood and Lakeport, both of which support the 1066MHz FSB (as well as 800) and Dual Channel DDR-2 667 and 533. Glenwood (the successor to 925X) will support up to 8GB of memory, making it the perfect candidate for EM64T enabled processors that want to break the 4GB barrier.