Multimedia extensions (MM8),
single-instruction multiple data
(SIMD) handling routines, and
(yper-Threading were all special-
iZed new CPU instruction sets that
were slipstreamed or hturned onv
in existing chipsets after the
release of a new CPU.
Typically, chipset design
teams—who work closely with the
CPU design teams—know well in
advance what new CPU features
are on the drawing board, and are
able to build chipsets that will
accommodate new instruction sets
and features. In some circumstanc-es, however, a brand-new chipset
has to be created.
A short but powerful example of
these first two steps is this
Legions of fanatic high-end PC
gamers provided CPU manufactur-
ers with not only a very specific
usage model, but also a hungry
consumer base willing to pay
more for extra performance. As a
result, Intel released the Pentium 4
%xtreme %dition with its huge 2MB
Level cache and the perfor-
mance-oriented 75P chipset.Step 3: Virtually Prototype
the CPU Supermodel
Once all the data has been gathered
and the usage model created, the ini-
tial designs are produced in the form
of two computer models—logical
and physical.
The logical model is a kind of
block diagram that describes how the
various parts of the CPU should work
together and where they should be
placed. In other words, how can the
75 million transistors be arrangedNOVEMBER 2004 MA XIMUMPC 57
It may look like a space-age serving tray
(think diplomatic meals on the Enterprise), but
it’s actually hundreds of CPUs etched into a
giant silicon disc. Each CPU will soon be cut
away with lasers, and then individually tested
for speed and reliability.ËTo reduce the risk
of contamination,
chipmakers often
go commando
under their bunny
suits.