Pentium processors

The Pentium brand name initially referred only to the fifth-generation microarchitecture of microprocessors from Intel, called Intel P5 and described here, but later it covered also subsequent generations. So, the Pentium as Intel P5, considered here, was a successor to the 486 line, and was first shipped on March 22, 1993.

The Pentium was expected to be named 80586 or i586, to follow the naming convention of previous generations. However, Intel was unable to persuade a court to allow them to trademark a number (such as 486), in order to prevent competitors such as Advanced Micro Devices from branding their processors with similar names (such as AMD's Am486).

Intel enlisted the help of Lexicon Branding to create a brand that could be trademarked. The Pentium brand was very successful, and was and still is maintained through several generations of processors, from the Pentium Pro to the Pentium Extreme Edition and further. Although not used for marketing purposes, Pentium series processors are still given numerical product codes, starting with 80500 for the original Pentium chip.

Intel has now largely retired the Pentium brand and replaced it with the "Intel Core" brand, although it is still used on a line of value processors called Pentium Dual-Core[1]. The first Intel Core, released in January 2006, extended the Pentium M microarchitecture. The Intel Core 2, released in July 2006, features the new Intel Core microarchitecture.


Microsoft and many other companies use the original Pentium as a standard for specifications of requirements. For example, Microsoft's stated requirements for the Microsoft Visual Studio 2005 Team Edition, include (at least) a Pentium processor running at a clock speed of 600 MHz (required), or 1 GHz (recommended). To find out if another processor meets the requirement, a conversion must be used that gives its speed in terms of standard Pentium clock rates. For example, a Pentium Pro would meet the requirement running at a much lower clock speed, because of its more advanced architecture. An equivalency chart is usually used to compare more modern processors to find out if they meet this requirement.

In programming, it is sometimes necessary to distinguish the original Pentium processor architecture from later (P6 or P68-based) Pentium-branded architectures. For these cases, i586 is a common, though spurious, way to refer to the early Pentium processors, as well as processors made by Intel's competitors that can run machine code targeted to the early Pentiums.