Benchmark testers and analysts who've test-driven the super-fast chips generally agree that Intel's 1-GHz Pentium III holds a performance margin over AMD's 1-GHz Athlon when it comes to running 3D applications, games and other programs.
The gap isn't huge--and will likely get thinner when AMD releases a new Athlon code-named Thunderbird toward the middle of the year--but it exists.
"Intel's 1-GHz Pentium III is the clear winner on our run of benchmarks," stated analysts at TheMeter, a testing site run by influential analysts Dean McCarron and Mike Feibus of Mercury Research. "While AMD managed the first 1-GHz announcement, Intel is emerging as the performance leader at this level--at least for now."
Pentium III's edge comes from a couple of different factors, but mostly it derives from differences in arcane aspects of the chip's architecture. Chief among these is the secondary cache, a memory reservoir that keeps the core of the chip stocked with data.
The "Coppermine" Pentium IIIs, which first came out last October and include the 1-GHz, come with a 256KB cache that is integrated on the same piece of silicon as the processor core. The cache also runs at the same speed as the processor and can pass 256 bits to the processor at once, rather than the more traditional 64 bits.
Athlon has a cache that is twice as large, but it is located on separate chips that reside next to the main chip. The Athlon cache also runs at slower speeds and passes less data to the processor per cycle.
Roughly speaking, the difference means that the Pentium III looks more like an airport where the passengers go from the terminal to planes on jetways, while the Athlon is like one of those airports where passengers have to take buses to the airplane. The processor core simply gets more data at a faster, more consistent rate. Athlon won't come with an integrated cache until Thunderbird.
The Pentium III also appears to take better advantage of Microsoft's latest version of Direct X, according to The Meter. The 1-GHz Pentium III outscored Athlon on tests centered on the games Quake III and II as well as other 3D tests. Testers at Sharky Extreme and Anandtech found similar results.
Most of the testers pitted a Pentium III containing fast Rambus memory against a 1-GHz Athlon containing standard memory, called SDRAM, running at 133-MHz. Anandtech tested Intel computers with both types of memory but still found a slight Intel lead in many instances. Still, Athlon enjoyed an edge when running professional graphics applications, Anandtech found.
"The Coppermine product, if it has a reasonable memory system behind it, and by reasonable I mean Rambus RDRAM or 133 SDRAM, will provide better performance on many benchmarks than the 1-GHz Athlon," said Nathan Brookwood, an analyst at Insight 64. "And as long as Intel has an advantage, they will promote it."
Still, he added that the edge is thin and subject to change.
"I don't think there is any way for a person to say one is superior to another in all regards," he said.