An analyst expressed doubts about demonstration of a “real” dual-core microprocessor during an Intel’s recent demonstration at Intel Developer Forum Fall 2004 in San Francisco, California. Insight 64’s Nathan Brookwood believes that Intel most likely showcased a dual-processor system instead of a dual-core processor-based system during the show.

At last week’s Developer Forum, Intel demonstrated how its Digital Office vision might enable three workers in different locations to collaborate to solve a complicated problem. One of the workers (“Jason”) had to juggle several compute-intensive tasks on his system, but the work flowed easily without the sorts of fits and starts that would plague many contemporary systems. At the conclusion of the demo, Bill Siu, the General Manager of Intel’s Desktop Platforms Group, casually noted that “Jason was using a dual-core system on a 915 [i.e., Grantsdale] platform.” When asked about it later during a Q&A session, Siu smiled coyly, and added only that the system used “an engineering prototype” of a dual core processor with “real silicon.” This begs the question of what was really inside the box.

Nathan Brookwood, the principal analyst for Insight 64 believes there are three options of what Intel might demonstrate.

“The least likely scenario is that the demo used the first silicon samples of the dual-core product planned for release next year. Intel did demo the first silicon for its dual-core Itanium, and AMD had just demonstrated the first silicon for its Opteron processor the week prior to IDF. We believe that if Intel actually had achieved this milestone, it would have trumpeted the news far more loudly and widely; their awesome PR machine would have made sure everyone on the planet was aware of this accomplishment. So we discount this theory completely,” Nathan Brookwood writes.

“It is a bit more likely that Intel crammed two of its current Pentium chips into a single package that could be plugged into the socket of a 915 motherboard. (This is known as a multi-chip package (MCP), and has been used for years in certain applications.) The standard P4 package measures about 30mm on a side, and could conceivably hold many discrete processors that only measure about 11mm on a side. Intel wouldn’t do this just for an IDF demo, but the resulting MCP might be useful for evaluating dual-core platforms, especially if the initial dual-core design follows the scheme we outlined above. The system would certainly be consistent with Siu’s claims of “dual core,” “915,” and “real silicon,” Mr. Brookwood claims.

“It is even more likely that Intel merely designed a dual-processor motherboard around its 915 chipset. The 915 is normally used only in uniprocessor designs, but there is no reason why engineers inside Intel could not circumvent the restrictions that prevent Intel’s customers from using the 915 in DP configurations. Designing a unique motherboard is clearly less expensive and takes less time than creating a multi-chip package, and the resulting system would come close to replicating the performance of the eventual dual-core product. Like the MCP scenario, this system would fit with Siu’s claims of “dual core,” “915,” and “real silicon,” Insight’s 64 principal analyst concludes, leaving the readers to decide what exactly did Intel showcase.

The analyst notes that typical Intel-based SMP systems, such as those fuelled by Intel Xeon processors, have processor system bus bottleneck, as all the chips have to share one PSB, be it a 400MHz QPB for 4-way systems or 800MHz PSB for 2-way systems. It is believed that dual-core processors will also have to share the same bus, which may limit their performance, even though by the time dual-core desktop chips are available, Intel will also present 1066MHz infrastructure for such microprocessors.

Intel and AMD both showcased functioning dual-core processors for servers: Intel Itanium 2 "Montecito" and AMD Opteron "Egypt".

Intel did not comment on the story.