Editing Pentium (original) (section)

== Overview ==
The P5 Pentium is the first [[superscalar processor|superscalar]] [[x86]] processor, meaning it was often able to execute two instructions at the same time. Some techniques used to implement this were based on the earlier superscalar [[Intel i960]] CA (1989), while other details were invented exclusively for the P5 design. Large parts were also copied from the i386 or i486, especially the strategies used to cope with the complicated x86 encodings in a pipelined fashion.<ref>as compared to a simple RISC processor like the i960.</ref> Just like the i486, the Pentium used both an optimized microcode system and RISC-like techniques, depending on the particular instruction, or part of instruction. The dual integer [[instruction pipelining|pipeline]] design is something that had been argued being impossible to implement for a [[Complex instruction set computer|CISC]] instruction set, by certain academics and RISC competitors.{{Who|date=March 2024}}

Other central features include a redesigned and significantly faster floating-point unit, a wide 64-bit [[Bus (computing)|data bus]] (external as well as internal), separate code and [[data cache]]s, and many other techniques and features to enhance performance. 

The P5 also has better support for multiprocessing compared to the i486, and is the first x86 CPU with hardware support for it similar to IBM mainframe computers. Intel worked with IBM to define this ability and also designed it into the P5 microarchitecture. This ability was absent in prior x86 generations and x86 processors from competitors.

In order to employ the dual pipelines at their full potential, certain compilers were optimized to better exploit instruction level parallelism, although not all applications would substantially gain from being recompiled. The faster FPU always enhanced floating point performance significantly though, compared to the i486 or i387. Intel spent resources working with development tool vendors, [[independent software vendor|ISV]]s and [[operating system]] (OS) companies to optimize their products.

[[File:Intel Pentium A80501 66 SX950.JPG|thumb|Intel Pentium A80501 {{nowrap|66 MHz}} SX950 die image]]

Competitors included the superscalar [[PowerPC 601]] (1993), [[SuperSPARC]] (1992), [[Alpha 21064|DEC Alpha 21064]] (1992), [[AMD 29000|AMD 29050]] (1990), [[Motorola 88000|Motorola MC88110]] (1991) and [[Motorola 68060]] (1994), most of which also used a superscalar in-order dual instruction pipeline configuration, and the non-superscalar [[Motorola 68040]] (1990) and [[R4000|MIPS R4000]] (1991).

=== Etymology ===
The name "Pentium" is originally derived from the [[Greek language|Greek]] word ''[[wiktionary:pent-|pente]]'' (''πέντε''), meaning "five", a reference to the prior numeric naming convention of Intel's 80x86 processors (8086–80486), with the [[Latin]] ending ''[[-ium]]'' since the processor would otherwise have been named 80586 using that convention.