|
IC
Engineering, it's an exacting science. When a
Design Engineer or Engineering Manager sits down to
architect his or her next chip, there are a myriad
of decisions that must be made that will affect the
outcome of their efforts. Designing a modern
day microprocessor is a daunting task.
When you
are doing things from the ground up, as did the
Intel design team with the Pentium 4, you need
to design not only with more than just current
application and performance expectations in mind but
with insight many years into the future. Just
think how long the P6 architecture of the original
Pentium processor has been around and you'll get the
idea.
Let's look at one simple
aspect that is the yard stick for most modern PC
Microprocessors, that being clock speed. Let's
face it folks, when John Q. Public steps into the
Computer Superstore with his hard earned cash in
hand, most times the clock speed in MHz. is the only
number that is stuck in his head. Now,
the original Pentium processor and P6
Micro-architecture was released at 60, 66 and what
was then a blazing 90MHz. Intel is just now
hitting the end of the line with that architecture
some 5 years later and at more than 10X its original
clock speed. So, obviously the engineers at
Intel needed to design things such that clock speed
scalability was a primary feature that would propel
them through many years of future roadmap
development.
For
sure, the number of clock cycles in a given time
frame, that a processor can serve up, is a major
factor with respect to performance. However as
you are aware, what that processor can do with that
incredibly high number of clock cycles, is just as
important. Since its introduction in November
of 2000, the Pentium 4 has been turned up well
beyond its 1.5GHz. introductory clock speed.
In this article we intend to show you what Intel's
latest MHz. Monster can do with those clock cycles,
now at a somewhat magical sounding 1.7GHz.
 |
| Specifications
Of The Pentium 4 NetBurst Micro-Architecure |
| .18
Micron, 42 Million Transistors with
headroom to spare |
|
-
Introductory
1.4GHz. and 1.5GHz. Clock Speed with roadmap
to 2GHz. and beyond
-
400MHz.
"Quad Pumped" System Bus
-
"Hyper
Pipelined" Technology - 20 stage
pipeline depth for greater frequency capability
-
"Rapid
Execution Engine" - ALUs run at
twice the speed of the core frequency
-
256K
L2 Advanced Transfer Cache running at core
processor speed
-
8K
L1 Data Cache
-
Execution
Trace Cache - Caches decoded Micro-Ops
readying them for execution
-
Advanced
Dynamic Execution - More efficient
speculative out of order execution unit feeding
execution engines
-
Enhanced
Branch Prediction Capability - Compensates
for the deeper pipeline's higher likelihood of
mis-predicted branches
-
Streaming
SIMD Extension 2 (SSE2) - 144 New
instructions including 128bit SIMD Integer
Arithmetic and 128bit double precision floating
point instructions in addition to SSE and MMX
instructions.
Click
images for full view
Here
we have your basic Pentium 4 chip. Yes, it
looks the same as the 1.5GHz. CPU that Intel sent us
in November, with the small exception of the 1.7G
marking on the lower right corner. We won't go
into much detail on the Pentium 4 architecture and
its feature set. If you need a refresher,
check our Pentium
4 Bench Test article from November of
2000. This CPU runs on the same 400MHz.
"Quad Pumped" System Bus that is supported
by RDRAM and the i850 chipset. Finally, this
Pentium 4 also is based on the same "Hyper
Pipelined" technology that drives its 1.5GHz.
predecessor and will drive its successors for years
to come. This 20 stage pipeline really allows
the P4 to crank up in clock speed. However, it
also means that it will execute less per clock
cycle. In short, this is a sort of "brute
force" approach to computing. If Intel
can get the frequency and bandwidth of the P4 up
high enough, the MHz. battle can be won against its
arch rival AMD, as well as overall system
performance leadership.
Sounds
like good science and engineering, right?
Let's see if things add up.
Good
Cooling, a new Motherboard from Abit and
over-clocking
|
