
                   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.




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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.

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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.




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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.
