The K6-2 is an x86 microprocessor introduced by AMD on May 28, 1998, and available in speeds ranging from 266 to 550 MHz. An enhancement of the original K6, the K6-2 introduced AMD's 3DNow! SIMD instruction set and an upgraded system-bus interface called Super Socket 7, which was backward compatible with older Socket 7 motherboards. It was manufactured using a 250 nanometer process, ran at 2.2 volts, and had 9.3 million transistors.