Pentium III is more like Pentium 2.1
by Alan Zisman (c)
published in Canadian Computers Wholesaler, March 1999
The changeover from Intel?s original Pentium to its
Pentium-II models was a big one, one that in many ways, the industry
While Intel has abandoned the Pentium (and
Pentium-MMX) Socket 7 design,
it remains in use by Intel?s competitors?and one of those competing
7 CPUs, AMD?s K6 model line, powered the most computers sold at retail
last year?out-selling any of Intel?s models.
But in bringing out the Pentium-II design, Intel tried
to push the industry
to adopt the company?s proprietary Slot One design?putting the
its cache RAM, and its support chips onto a large cartridge. Even
low-end model: Celeron, adhered to the Slot One standard, requiring
P-II designs also came with Accelerated Graphics Port
(AGP) video, though
that?s now available on a few, high-end Socket 7 boards. And most
they?ve pushed the system bus up from 66 MHz to 100 MHz.
But it?s the end of the road for the P-II series.
Intel has announced
the Pentium-III, which should be shipping as you read this. But don?t
anywhere near as traumatic a transition as last time around. In fact, I
doubt that the new product line is really deserving such a dramatic
If we think of Windows 95 as Windows 4.0?a major break
from its Windows
3.1 predecessor, then last year?s Win98 would have been Win 4.1.
the Pentium-II design was a major break from its Pentium predecessor,
the P-III is more like a Point-one upgrade.
Unlike the drastic design changes necessitated to
handle the P-II, the
new models are slot-compatible. They will continue to use the Intel
motherboard chipsets used by the current generation of P-II designs.
wanting to upgrade current P-II systems will need to upgrade their
Bios, however?so don?t expect to simply pop a new P-III into an
P-II computer. CPU speeds will, at least initially, not be much, if any
faster than high-end P-IIs, with 450 MHz and 500 MHz models replacing
and 450 MHz P-IIs?and continuing to run on a 100 MHz system bus.
In fact, there will be only one major difference
between a 450 MHz P-II
and a 450 MHz P-III. The newer CPU includes what Intel formerly
the Katmai New Instruction set?a collection of 70 new low-level
instructions, designed to improve multimedia performance and more.
is targetted at voice recognition, streaming video, and improved
Sounds like MMX, doesn?t it? MMX, appearing in early
1997, was also
a group of new processor instructions, aiming at bettering multimedia
MMX was first added to Pentium-level processors, with compatible
sets soon appearing in most of the Pentium-clone processors as well.
In retrospect, MMX was less than a revolution, its
more promise than reality. The problem was that software had to be
coded to take advantage of MMX features, and with a few exceptions, not
much was. Even game companies have been more likely to produce versions
optimized for various 3D add-on cards than to write MMX-specific
Will the same fate await the Katmai instructions?
We?ll have to wait
and see. Microsoft has promised to build support for Katmai into its
Windows 2000 operating system. But unlike MMX, Intel?s competitors seem
self-confident enough to go their own route?a non-compatible set of new
processor instructions being called ?3D Now!?.
Whether Katmai turns out to matter or not, P-III based
rapidly become available, mostly because they require such minor
from existing P-II systems.
And the P-III is clearly the direction that Intel
mainstream systems, at least for the next little while. Intel?s Greg
brand manager for the P-III claims that with the P-III?s release, there
will be no new versions of its predecessor.
And expect design changes in the future, to support
P-III models. Look forward to a 133 MHz bus speed, later in 1999,
new chipsets, in the opinion of Ming Chok, vice president of
manufacturer Soyo. There will also be a sped-up 4x version of AGP,
requiring system revisions. CPU speeds should reach 600 MHz late this
At the same time, Intel is planning to revise and
simplify the Slot
One design for P-IIIs towards the end of the year, according to the
Paul Otellini, executive vice president of the Intel architecture
group. All these changes will mean that later P-III models will no
be compatible with current systems?but the pace of change will be more
gradual than we?ve seen in the recent past.
In fact, Otellini suggested, Intel is hoping that
system designs and
motherboard chipsets will be able to last over two generations of
to complaints from manufacturers forced to too quickly change their
Ironically, while Intel is trying to slow the
sometimes frantic pace
of change, competitor AMD, which has been successfully building more
more powerful processors compatible with the older Socket 7 designs is
trying to achieve a dramatic break with its past.
While its new and improved 450 MHz K6-3 remains a
Socket 7 model, it
appears to be the end of that evolutionary pathway. The upcoming K7
will use a Slot One-like technology to run at 500 MHz and above, with
company aiming for speeds as high as 1000 MHz sometime in 2000, as the
company switches from aluminum to copper technology. The initial K7s,
last October and due mid-1999, are expected to run on an innovative 200
MHz system bus, built using Digital?s advanced Alpha EV6 bus
While this will certainly provide real performance improvements, the
will be on AMD to convince system manufacturers to build motherboards
systems based on it.
The result will be Intel and AMD switching roles, with
systems only slowly evolving from current standards while promising
modest performance improvements. AMD, on the other hand, is taking over
Intel?s traditional role of promising dramatic performance improvements
to manufacturers willing to make an equally dramatic break with current