The Pentium II is an x86 architecture microprocessor by Intel, introduced on May 7, 1997. It was based on a modifed version of the P6 core first used for the Pentium Pro, but with improved 16-bit performance and the addition of the MultiMedia eXtension (MMX) instructions which had already been introduced on the Pentium MMX.
The original Klamath Pentium II ran at 233 and 266 MHz, were produced in a 0.35 µm fabrication process and produced (for that time) an incredible amount of heat. They also worked with a 66 MHz front side bus, which was a speed that was inadequate for the CPU's design to show its full potential. A 300 MHz version was released later in 1997.
