Apparently chafing under the invisible restrictions of
Moore's law, Intel and AMD spent 2004 searching for ways of further improving
processor designs that had virtually reached their maximum speeds under current
manufacturing technologies. Both companies changed processor naming schemes and
tinkered with cache sizes, while Intel flirted with changing the basic design of
the Pentium 4 to mirror that of its highly successful Pentium M mobile CPU.
AMD was apparently first to hit on a
possible answer to the dilemma facing them. If one chip was good, two chips must
be better! Multiple CPU machines have existed for years at the
business level, and the performance advantages are well understood, so why not cram two
cores into a single processor die and bring multiprocessing to the
Predicably, both companies dived head
first into this new market, promising (and eventually delivering)
dual-core desktop processors and chipsets. Intel split its dual-core offerings
into two product lines; the high-end Pentium Extreme Edition clocked at
3.2GHz using the company's Hyperthreading technology, and the mainstream Pentium D 840,
830 and 820 processors clocked at 3.2GHz, 3.0GHz and 2.8GHz respectively without
As the Intel Pentium Extreme Edition is priced beyond the grasp
of most consumers, PCSTATS has opted to forego that CPU in favour of
the flagship Intel Pentium D 840 processor, clocked at a
respectable 3.2GHz and retailing for about $740CDN ($650USD). I should also mention our thanks to DAIWA Distribution for helping to facilitate this review.
This 90nm processor uses a pair of Prescott
cores running at 16 x 200MHz to bring multi-processing to the desktop in a
LGA775 pinless package.
The most obvious new feature of the LGA775 Intel Pentium D 840 processor is its dual-core nature.
The processor is literally composed of two Prescott Pentium 4
cores stuck together with a pair of interfaces to the system bus. We'll
cover the technology behind Intel's approach to dual-core more a little
later in the review.
Pentium D line of processors (models include 820, 830 and 840) are built on the 90nm process
and incorporate 230 million transistors. The Intel Pentium D 840 has a
maximum power requirement of 130Watts (as opposed to 169million transistors and 115W for the 3.8GHz P4
670). Each core has access to its own L1 and L2 cache memory, 16KB
and 1MB respectively. All current dual core processors use the
800MHz FSB like traditional Prescott Pentium 4s, and currently are only
supported on DDR II memory platforms. We'll cover the available chipsets
for the Pentium D in a moment.