MA XIMUMPC SEPTEMBER 2006
Intel Core 2 Extreme X
The new Conroe CPU delivers in a big way, with plenty of horsepower to spare
CPUYears ago, when Intel was invin-
cible and held the performance
crown with an iron fi st, we used to
hear conspiracy theories that the
company secretly had access to
extraterrestrial technology. You’ve
heard tales of the agreement
between Intel-founder Robert
Noyce and then-President Truman
over the Roswell tech, right?
OK, as kooky as that sounds,
Intel’s new dual-core CPU—the
Core 2 Extreme X6800—seems
pretty otherworldly. It’s that spooky-
cool and scary-fast. Running at its
stock 2.93GHz clock speed and
under full load, the processor sim-
ply doesn’t get hot. We thought
we had it wrong, so we unplugged
the power to the heatsink fan,
loaded up the proc again, and it
still ran for hours.
The part that’ll make you most believe
the MiB angle, however, is this proc’s
performance. We’re not talking about
the little 5 percent clock
bumps and performance
“jumps” that we’ve all
become accustomed
to over the last few
years—this is signifi -
cant. In fact, prepare
to create some
new superlatives
for this processor
because the ones we have just
don’t do justice to the new architecture.
Think “fastiest” or “stupenderiffi cier.”
We aren’t kidding. When we were
still debating our CPU pick for the Dream
Machine, we fi red up the C2E with the
same videocard, hard drive, and drivers
that we used last month to benchmark
AMD’s AM2. The result? The C2E posted
an unheard of 32 to 70 percent perfor-
mance increase on CPU-bound tests. Let’s
say that again: 70 percent! In other words,
this suckah is so fast, it should have itsown theme song and an entourage that will
push you to the curb if you get too close to
its black C2E-style Escalade.
The CPU wars haven’t seen this kind
of all-out ass-kicking in the last decade.
The original Athlon 64 FX-51 was fast
when it launched, but it didn’t put the hurt
on Pentium 4 like this. The performance
of the Core 2 Extreme X6800 is so outside
the box, we wonder if Intel’s found a new
cache of fastier, post-Roswell UFO tech-
nology from which to fashion this CPU.
Publicly, Intel attributes the stellar
performance to several factors in the
new Core microarchitecture, which is an
evolutionary offshoot of the Pentium M
core. The Core 2 Extreme features a
slightly longer 14-stage pipeline (versus
12-stages in the Yonah core used for
the Core Duo and Pentium M). The Core
microarchitecture is also “wider” with the
ability to crunch four instructions at the
same time, versus three in the Core Duo
and Pentium 4. The C2E is also able to
process a single 128-bit SSE instruction
in one cycle, whereas the Athlon 64 and
Pentium 4 take two.Unlike Presler in the Pentium
Extreme Edition 965, which used
two independent CPU cores
adjacent to each other, C2E is
a “monolithic” chip with both
cores residing on the same die.
Because the two CPU cores in
Presler were separate, the chips
could not share information
between their L2 caches without
having to cross the slow front-
side bus. With the monolithic
C2E, both cores have full access
to the L2 cache, which can be
allocated on the fl y depending on
the task. If just one core is busy,
it can use the entire 4MB cache
while the other processor naps.
The prefetching routines in this
CPU are also greatly improved,
so the chip’s L2 caches are con-
stantly churning the needed data and
rarely have to reach out to slow main
memory. According to Intel, the prefetch
routine is so good that it effectively
ameliorates main-memory latency and
bandwidth issues. The company also
claims that a survey of the front-side
bus activity shows that it’s very diffi cult
to saturate the FSB with enough data to
impact performance.
The CPU comes in the familiar LGA
package, runs on the standard 1066MHz
bus, and fi ts in most standard Intel boards.
However, you can’t assume it will work
on older boards. Because the Core 2 Duo
and Core 2 Extreme use less power than
the Pentium 4, Pentium D, and Pentium
Extreme Editions, the motherboard’s volt-
age-regulation circuits have to support the
lower voltage of the new chip.
For the last couple months, we’ve
recommended that you hold off on pur-
chasing a LGA775 mobo without Core 2
Duo/Extreme support and we’re glad we
did. This chip truly makes everything that
came before—be it Athlon or Pentium—
seem sluggish.bumps and performance
“jumps” that we’ve all
become accustomed
to over the last few
years—this is signifi -
cant. In fact, prepare
to create somefor this processor
because the ones we have justbumps and performance
“jumps” that we’ve all
become accustomed
to over the last few
years—this is signifi -
cant. In fact, preparebecause the ones we have justThe Core 2 Extreme features both cores on a single die
instead of two separate dies. Early next year, Intel will
jam two dual-core Core 2, um, cores into a single die to
make its quad-core processor.Dream
Machine
Behold the Hardware!
7e GiVe YoU A PArt
BY
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