Instead, Intel will boost performance on its chips by increasing the size of the cache, a pool of memory located on the processor for rapid data access. Current mainstream Pentium 4s now have 1MB cache. In the future, these chips will have 2MB of cache, like Intel's Xeon server chips and the "Extreme Edition" Pentium 4s designed for gaming PCs.
Intel will continue to come out with Extreme Edition chips by boosting the bus speed and cache size, said Bill Kirby, director of platform marketing at Intel.
The first mainstream Pentium 4 with 2MB of cache will run at 3.8GHz and come out early next year, an Intel representative said. Larger caches will then cascade down the Pentium 4 product line, the representative added.
The chipmaker also intends to emphasize more sharply technologies such as 64-bit functionality, HyperThreading and a security technology called LaGrande. It will also increase development efforts on dual-core chips with the goal of a 2005 release.
Behind the shift is Intel President Paul Otellini, who wants the company to move away from focusing on increases in chip speed, measured in megahertz, as the primary way to increase performance. Intel has talked about such a shift for years, but remained fond of the clock-speed approach until recently. Speeches by executives about moving away from megahertz were often closely followed by announcements of faster chips.
Technically, Intel could likely come out with a 4GHz chip, said Dean McCarron, principal analyst at Mercury Research. Hobbyists are already running Pentium 4s at 6GHz, and game machine specialist Alienware is selling an overclocked 4GHz system.
On the other hand, Intel would have to put so many engineering and testing resources into qualifying a 4GHz Pentium to work in all conditions that the cost would far outweigh any financial benefit. Because Intel's dual-core chips are set for release in 2005, only a few thousand 4GHz chips would likely have been sold, McCarron said.
Problems with power consumption and heat that accompany megahertz increases are likely another spur for the change. Processors with larger caches or two cores can run at lower speeds than conventional chips--hence they produce less heat and consume less energy, but provide better performance. "Hot spots"--high energy centers on chips that crank out heat--can also be spread out or reduced.
To further reduce power consumption, the company plans to begin in 2007 to produce a desktop chip code-named Merom. The processor is based on the more energy-efficient architectures from Intel's notebook chip line-up.
Chips with larger caches can be more expensive to make, because fewer can be produced out of a single wafer. Two factors, however, will soften the overall impact of a larger chip size. Earlier this year, Intel shifted to the 90-nanometer manufacturing process, which leads to smaller chips. The company also said that, because of an inventory surplus, it will scale back production in the current quarter.