Intel Pentium 4 Aka Prescott In Detail
It looks like millions of other Pentium 4 processors, but there's something new: 1 MB L2 cache, 16 kB L1 data cache and SSE3, the fourth instruction set that Intel adds to the Pentium family (MMX, SSE, SSE2).
Prescott was scheduled for autumn, but it was delayed to late winter. Was Intel having problems with its 90 nm process? Or was the delay part of Intel's strategic considerations?
We believe there were manufacturing problems, due not to the cutting-edge 90 nm process, but to the difficulties of the Prescott design. Two factors support our speculation: On the one hand the Prescott processor becomes much hotter than Northwood at similar clock speeds. The four degrees Centigrade difference we measured at one side of the Zalman coolers we used add up to at least double the number inside the processor. On the other hand, Intel hesitates to ship Prescott processors at 3.4E GHz yet.
Intel's nomenclature is very simple, as they basically only add an E after the clock speed number, e.g. Pentium 4 3.0E GHz. Besides the three versions we reviewed in this article (2.8E / 3.0E / 3.2E GHz), Intel also is launching a low-cost Prescott version at 2.8A GHz and 133 MHz FSB speed without HyperThreading. This model is uninteresting for the retail market, but is still a major contribution to Intel's corporate claim that it has a wide-range processor offering.
Handling Prescott is basically no great deal: It still requires socket 478, so Intel simply had to update the specifications. That is of particular importance as the TDP (thermal design power) reached a new record: It is 103 Watts for the 3.4E and 3.2E GHz versions.
Even more interesting is the TDP of the new P4 Extreme Edition at 3.4 GHz: 102.9 Watts. While the TDP is the maximum thermal dissipation loss, we were able to feel and measure temperature differences between the Extreme Edition 3.4 and the 3.2E GHz at the expense of Prescott.