Pentium 4: More speed in the pipeline

The Santa Clara, Calif.-based chipmaker is coming out with a new chipset, code-named Springdale, for Pentium 4 PCs. The chipset runs at 800MHz, substantially faster than the 400MHz and 533MHz chipsets currently available for Pentium 4 computers, according to sources close to the company.

The new chipset will be released with a 3.2GHz version of the Pentium 4, the sources said. Intel could not be reached for comment.

Among other tasks, the chipset creates a data path, or system bus, between the processor and a computer's memory. Speeding it up increases both the rate the processor can obtain data and the amount that can be transferred.

The imbalance between processor speeds, which top out at 3GHz, and memory and system buses, which are far slower, has made the system bus look more like a street than a freeway because of the imbalance. Often, processors hum along in idle mode because of a lack of data. Likewise, latency, the time gap between when a chip has requested data and when it arrives, has grown.

"Anything you can do to speed that up will help," said Nathan Brookwood, an analyst at consulting firm Insight 64.

Overall, the increase in bus speed could boost performance by 3 percent to 5 percent, he said.

The chip is expected to be discussed at the Intel Developer Forum kicking off in San Jose, Calif., on Feb. 18. Earlier, some analysts speculated that Springdale would come with a 667MHz bus. Desktop chip price cuts, which haven't occurred since November, will also likely occur around the same time to ease the introduction of the 3.2GHz chip.

The Springdale chipsets likely will invigorate the ongoing performance duel between Intel and rival Advanced Micro Devices. Although the top chips from the two companies were fairly evenly matched in 2001, Intel began to pull away on various benchmark tests from AMD in the second half of 2002 by increasing the clock speed, measured in mega- and gigahertz, on the Pentium 4 faster than AMD did with its competing Athlon chip.

Goosing megahertz isn't everything in performance, but it helps, analysts and executives say.

AMD had to delay some chips and has had difficulty producing its fastest ones in appreciable volumes.

Intel then widened the gap further with the release of the 3GHz Pentium 4 in November. The chip was the first desktop part to come with hyperthreading, which allows a chip to perform multiple tasks at a single time. Despite some early skepticism, benchmark testers gave it the thumbs up.

"We have to hand it to Intel; we honestly expected hyperthreading to be a big flop initially on the desktop because of losses in performance," Anand Lai Shimpi, editor of the Anandtech site, wrote at the time. "Hyperthreading in its current form is very much an infant technology; the potential for it is huge, and it can grow into something much larger than what we see here today."

AMD, though, will counter with its Athlon 64, the first desktop chip based around the Hammer architecture, in late March or early April. Hammer chips will come with an integrated memory controller--the part of the chipset that creates the system bus--that will run at the same speed as the chip, making it faster than Intel.

Sunnyvale, Calif.-based AMD has also made several tweaks to the core of Hammer, which will improve performance. The Hammer core is partly based on the Athlon architecture.

Both approaches have their advantages, but at this point "there are so many different factors...it is hard to determine" which will prove superior at any given speed, Brookwood said.