Intel Dual Core Performance Preview Part I: First Encounter

The Chip: Pentium Extreme Edition

As we mentioned in our IDF coverage, Intel has dropped the number 4 from their naming for their dual core parts.  The new dual core desktop CPUs will simply be called the Pentium D and the Pentium Extreme Edition. 

Both the Pentium D and Pentium Extreme Edition are nothing more than two 90nm Prescott 1M dies glued together.  That means that each core has its own 1MB L2 cache, and that also means that architecturally, these chips are no different than the single core Pentium 4s that are out today - other than the obvious dual core fact. 

Contrary to what we've reported earlier, the only difference between the Pentium D and the Pentium Extreme Edition is the presence of Hyper Threading; mainly, the Pentium D doesn't have it, while the Extreme Edition does.  Both chips will only use a 800MHz FSB, they both have the same cache sizes, and they only differ in the presence of HT. 

Armed with Hyper Threading, the Pentium Extreme Edition allows the execution of 4 concurrent threads and appears as a quad processor CPU to the OS.  Without Hyper Threading, the Pentium D only allows for 2 concurrent threads and appears as a dual processor CPU to the OS.

While the Pentium D will be offered in three speed grades, from 2.8GHz up to 3.2GHz, the Extreme Edition will only be launched at 3.2GHz.  Note that the fastest single core Pentium 4s run between 3.6GHz and 3.8GHz, so there is a significant clock speed penalty paid by going to dual core.