Following the K6, AMD launched the K6-2 one year after the first introduction of the K6 166 MHz. First version launched were clocked at 266, 300 and 333 MHz, then 350 MHz and more. They supported MMX and the new AMD's 3DNow! instructions set. This engineering sample was clocked at 66 MHz with a clock ratio of 5.5x. No date code on this sample, but the commercial K6-2 366 MHz was announced on November, 16th 1998