270 lines
10 KiB
Plaintext
270 lines
10 KiB
Plaintext
|
|
The PentiumTM Processor
|
|
Q & A
|
|
March 22, 1993
|
|
|
|
Background
|
|
|
|
On March 22, Intel Corporation announced production
|
|
shipments and technical details of its fifth-generation,
|
|
compatible processor, the PentiumTM processor. Pentium
|
|
processor-based system announcements will be made by
|
|
computer manufacturers beginning in mid-May.
|
|
|
|
General
|
|
|
|
Q1. Which markets will be the first to employ Pentium
|
|
processor-based systems?
|
|
|
|
A1. We expect that initial customers for Pentium processor-
|
|
based systems will be traditional early adopters who
|
|
require increased performance to meet their needs. The
|
|
Pentium processor will power advanced personal
|
|
computers, workstations and super servers.
|
|
|
|
Q2. I just bought an Intel486TM CPU-based system; is the
|
|
Pentium processor going to obsolete it?
|
|
|
|
A2. No. The Intel486TM CPU remains the mainstream processor.
|
|
The Pentium processor will have limited availability in
|
|
'93 and will be targeted at high-end applications, such
|
|
as servers. As we have seen with the Intel486 CPU,
|
|
the Pentium processor will evolve downward in the
|
|
market and one day become the volume mainstream
|
|
processor .
|
|
|
|
Speed/Performance
|
|
|
|
Q3. What is the performance of the Pentium processor in
|
|
comparison to an Intel486 CPU?
|
|
|
|
A3. The Pentium processor runs applications up to five
|
|
times as fast as the popular, desktop-standard 33-MHz
|
|
Intel486 DX CPU. The 66-MHz Pentium processor operates
|
|
at 112 million instuctions per second Dhrystone (MIPS),
|
|
it has a SPECint92 rating of 64.5 and SPECfp92 rating
|
|
of 56.9 and an Intel iCOMPTM Index rating of 567. The
|
|
performance delta between the 66- and 60-MHz version of
|
|
the Pentium processor is about 10 percent.
|
|
|
|
|
|
|
|
|
|
Intel/Page 2
|
|
Pentium processor
|
|
|
|
|
|
Q4. What is the performance of the Pentium processor in
|
|
comparison to RISC machines?
|
|
|
|
A4. The Pentium processor has equal or greater integer
|
|
performance (SPECint92) than all current volume
|
|
shipping RISC-based systems. In addition, the Pentium
|
|
processor has demonstrated workstation-class floating-
|
|
point performance.
|
|
The RISC processors available today are designed to be
|
|
a very high-end processors. In the mainstream volume
|
|
workstation and PC marketplace, it is important to be
|
|
able to ship millions of processors, not just
|
|
thousands.
|
|
|
|
Q5. What is the iCOMPTM Index?
|
|
|
|
A5. The iCOMPTM Index was created by Intel as an easy-to-use
|
|
index to give PC buyers useful processor performance
|
|
information when selecting an Intel-based PC. This
|
|
tool reflects the performance of the microprocessor and
|
|
should not be used as a measurement of overall system
|
|
performance.
|
|
For example, the Intel486 SX CPU at 25-MHz has an iCOMP
|
|
rating of 100, the Intel486 DX2 CPU at 66-MHz has an
|
|
iCOMP rating of 297 and the Pentium processor at 66-MHz
|
|
has an iCOMP rating of 567.
|
|
|
|
Naming
|
|
|
|
Q6. Why did you name it the Pentium processor?
|
|
|
|
A6. The purpose of naming it the Pentium processor is to
|
|
help users recognize the genuine Intel processor.
|
|
Imitators sell products using the "386" and "486"
|
|
designation when the products are not on par with
|
|
Intel's. We want to ensure that the PC user knows
|
|
which processor is the genuine Intel chip. The Pentium
|
|
name will designate that: no one else can legally use
|
|
that name.
|
|
|
|
Upgradability
|
|
|
|
Q7. I have heard people refer to Pentium Ready or OverDriveTM
|
|
Pentium systems. What are they and when will they be
|
|
available?
|
|
|
|
A7. Many Intel486 DX2 CPU-based systems will be upgradable
|
|
to Pentium processor technology. Whether systems are
|
|
upgradable is based on system design considerations.
|
|
The Pentium processor-based OverDriveTM Processor will be
|
|
introduced in 1994.
|
|
|
|
Intel/Page 3
|
|
Pentium processor
|
|
|
|
|
|
Software
|
|
|
|
Q8. What applications are best suited for Pentium processor-
|
|
based machines?
|
|
|
|
A8. The Pentium processor will enable high-performance
|
|
servers at a lower cost than currently available. The
|
|
Pentium processor is capable of running all major
|
|
network operating systems with scalability from the
|
|
desktop to the data center.
|
|
|
|
Performance-intensive desktop and technical
|
|
applications, such as imaging, real-time video and
|
|
voice recognition will benefit from the increased
|
|
performance available from the Pentium processor. In
|
|
addition, it will expand the acceptance of Intel
|
|
processor-based systems into applications such as
|
|
scientific modeling, computer-aided design/engineering
|
|
(CAD/CAE), large-scale financial analysis and high-
|
|
throughput client/server applications.
|
|
|
|
Q9. Will software written for 286/386/486 CPU-based systems
|
|
run on the Pentium processor? What will be the
|
|
difference?
|
|
|
|
A9. Yes, Intel has always been committed to compatibility
|
|
across processor generations and that will continue.
|
|
To achieve the highest possible software application
|
|
performance from Pentium processor and Intel486 CPU-
|
|
based systems, software can be optimized.
|
|
|
|
Q10. What is software optimization?
|
|
|
|
A10. Optimization is the process by which operating systems
|
|
and application software are developed or recompiled to
|
|
take full advantage of the Intel architecture. Results
|
|
are most dramatic on the Intel486 and Pentium processor-
|
|
based systems.
|
|
|
|
Q11. How much faster can the Pentium processor run today's
|
|
software than the Intel486 DX2 CPU?
|
|
|
|
A11. About 40-70% faster than the 66-MHz Intel486 DX2 CPU
|
|
running existing software.
|
|
|
|
|
|
|
|
|
|
Intel/Page 4
|
|
Pentium processor
|
|
|
|
|
|
Q12. Which software developers have committed to optimizing
|
|
their applications for the Intel architecture?
|
|
|
|
A12. Currently, Andersen Consulting*, Adobe*, Aldus*,
|
|
Autodesk*, Cadre*, Calera*, ComputerVision*, Dragon*,
|
|
EDS*, Frame Technology*, Gain Technology*, Gupta*,
|
|
Hypercube*, IBM*, Ithaca*, Interleaf*, Knowledgeware*,
|
|
Kurzweil*, Lotus*, Microsoft*, Novell*, NCR*, Oracle*,
|
|
Pixar*, Reuters*, SAS*, SCO*, Set Technology*, Sigma
|
|
Design*, SunSoft*, Sybase*, Univel*, Viewlogic*,
|
|
Ventura* Software, and Wolfram* have all committed that
|
|
one or more of their applications will be optimized for
|
|
the Intel architecture. More software companies are
|
|
committing every week.
|
|
|
|
Q13. Which operating system suppliers are committed to
|
|
supporting Pentium processor? When?
|
|
|
|
A13. IBM*, Microsoft*, NeXT*, Novell*, SCO*, SunSoft*,
|
|
Univel* and USL*. You will need to check with them on
|
|
announcement plans or ship schedules.
|
|
|
|
Q14. Which compiler and tools companies are supplying
|
|
optimized tools and compilers?
|
|
|
|
A14. Absoft*, Borland*, IBM*, Liant*, MetaWare*, Micro
|
|
Focus*, Microsoft*, NeXT*, SCO*, USL*, and WATCOM*.
|
|
|
|
Q15. If Pentium processor performance is so great, why would
|
|
I want or need to optimize my software?
|
|
|
|
A15. While the Pentium processor is significantly more
|
|
powerful than its predecessors, performance can be
|
|
enhanced when software is optimized for the Intel
|
|
architecture. Intel has been working with its software
|
|
partners for over a year to ensure that full advantage
|
|
of the Pentium processor and Intel486 microprocessor
|
|
performance can be taken by tools, compilers, operating
|
|
systems and application software.
|
|
|
|
Q16. How much incremental performance can I expect from an
|
|
optimized application running on a Pentium processor-
|
|
based system?
|
|
|
|
A16. Performance enhancements will vary, but early
|
|
optimization projects have yielded up to 30%
|
|
performance enhancement over the enhancement provided
|
|
by the chip alone.
|
|
|
|
Intel/Page 5
|
|
Pentium processor
|
|
|
|
|
|
Technical Details
|
|
|
|
Q17. How does the Pentium processor differ from the Intel486
|
|
CPU? What are new features of the Pentium processor?
|
|
|
|
A17. The Pentium processor includes both new architectural
|
|
features as well as enhancements to the Intel486 CPU.
|
|
New architectural features are superscalar
|
|
architecture, a totally redesigned Floating Point Unit
|
|
(FPU), branch prediction, separate code and data
|
|
caches, a write back cache with MESI (Mutual Exclusive
|
|
Shared Invalid) protocol, multiprocessor support and
|
|
built-in data integrity for increased reliability.
|
|
Other enhancements to the architecture include
|
|
hardwired instructions, enhanced microcode, increased
|
|
page size, 64-bit data bus and pipelining.
|
|
|
|
Q18. What is superscalar?
|
|
|
|
A18. Superscalar is new to the Pentium processor and is a
|
|
microarchitecture design technique that allows multiple
|
|
instructions to be executed simultaneously on chip.
|
|
(An anology: superscalar is like adding another lane to
|
|
a single lane highway; more cars (instructions) can go
|
|
to the same place at the same time).
|
|
|
|
Q19. What is branch prediction?
|
|
|
|
A19. Branch prediction is new to the Pentium processor and
|
|
is another performance improvement technique. Since
|
|
software execution incurs substantial delays on
|
|
branches, points in the software instruction stream
|
|
require a branch to a new, non-contiguous location in
|
|
system memory to fetch the next instruction. This
|
|
Intel-developed technology will predict where the
|
|
program is going next and can actually begin working on
|
|
the next instruction before it is actually called upon.
|
|
|
|
Q20. Why do you have separate data and instruction (code)
|
|
caches?
|
|
|
|
A20. Having the two separate caches allows the CPU to fetch
|
|
data and code in parallel, doubling the available cache
|
|
bandwidth. In addition, the Pentium processor has very
|
|
large on-chip data paths, some as large as 256 bits.
|
|
The data cache is dual access, meaning two instructions
|
|
can read and write data in parallel. This complements
|
|
the superscalar design (dual pipeline).
|
|
|
|
* Trademarks are the property of their respective owners.
|
|
Pentium, Intel486 and iCOMP are trademarks of Intel
|
|
Corporation.
|