Pentium is a brand used for a series of x86 architecture-compatible microprocessors produced by Intel on March 22, 1993, and code-named P5. The Intel Pentium was a replacement for the 80486 processor that originally sold for $878.00. The name Pentium comes from the Greek word for "five", pente, and is used because it was the fifth processor in the 80x86 line. It was supposed to be called the 80586, but the US court ruled that you cannot trademark a number. The Intel processors were available between speeds of 60 MHz and 300 MHz, had a 64-bit data bus, and had 1.9 million more transistors than the 80486DX (3.1 million).

The original Intel Pentium used a 273-pin grid array (PGA) form factor and ran on 5v power. Intel later released a second-generation on March 7, 1994, which included new processors from 75, 90, 100, 120, 133, 150, 166, and 200 MHz. The processors used a 296-pin staggered pin grid array (SPGA) form factor that is incompatible with the first-generation versions.

The third generation Pentium processors, code-named P55C, introduced in January 1997, incorporated the new technology MMX. The Pentium MMX processors were available in 166, 200, 233 MHz, and 266 MHz mobile versions.

Some other Intel Pentium processors include Pentium 4, Pentium D, Pentium M, and Pentium Dual-Core. When compared with other Intel processors, the Pentium processors are faster than Intel Celeron and Atom processors but slower than Intel's Core processors.

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