update As Intel prepares to brief the press and
analysts on the Pentium III today, reviews of the chip can already be found on Web
sites--and some are less than glowing.
These reviews, not for the uninitiated, are often couched in arcane chip-speak.
Aficionados, for example, may be impressed by front
and back shots of the processor board in a piece by Chamila
Sumanasekera at Review Zone.
But what may not strike people's fancy is the new processor's uncanny similarity to the
Pentium II, especially in performance
benchmarks listed on another site.
Like its older sibling, the Pentium III communicates with the cache memory at
half the speed of the processor. The cache memory on the high-end Xeon processor, on the
other hand, "talks" to the cache at full speed, or the same as that of the
processor, resulting in better performance.
Also, the sizes of the first and secondary caches are the same as the Pentium II: 32
and 512 kilobytes, respectively. Both caches are critical for boosting performance.
Generally speaking, the more cache, the faster the chip.
Like the Pentium II, it uses a 100-MHz bus, about 50
percent faster than the 66-MHz speed used on the Celeron processor, the mobile Pentium II
for notebook PCs, and the veteran Pentium MMX chip. But, again, no improvement over the
Pentium II.
Clock speeds, at least initially, are not very different. The top-of-the-line Pentium
II runs at 450 MHz, while the Pentium III will come out at this speed and at 500 and 550
MHz.
Prices are listed at Review Zone as $560 for the 450-MHz Pentium III and $780 for the
500-MHz version.
Other reviews are more critical about the similarities of the two processors of the
Pentium II and III.
"We're starting to wonder if perhaps Intel has another problem on its hands. You
have to understand that the core of the PII, the Celeron, and the PIII is more or less the
same core as the original Pentium Pro," according to ARS Technica, another Web
site that is offering a detailed technical preview of the Pentium III, including a number
of different benchmarks.
"This processor core started out at 150 MHz, folks. It's a good design, but Intel
may be reaching a point of diminishing returns on its sixth-generation [chip]."
Nevertheless, the Review Zone spells out important differences between the chips too.
Under "new media instructions," also known as "Katmai" instructions,
it lists as improvements MPEG encode
[creation] and decode (playback), 3D graphics, advanced AC3 audio, complex imaging
effects, and "realistic physics."
Applications, however, must be written to take advantage of these potentially powerful
instructions.
One underrated difference, according to Sumanasekera, is that the Pentium III consumes
less power then the Pentium II and only requires 1.8V.
But he cautions: "This is the real question about motherboard
support. Because although many motherboard manufacturers will offer BIOS updates for
their products to detect the Pentium III, you have to make sure your motherboard will also
support a voltage of 1.8V. Otherwise, you'll be providing the Pentium III with more power
than necessary, resulting in a slight increase in surface temperature," he said.
