AMD K6-2 and K6-2+ (Chompers) processors
Introduction: May 1998 (K6-2)
The K6-2 was a x86 microprocessor manufactured by AMD, available in speeds ranging from 266 to 550MHz. It had a 64KB Level 1 cache (32KB instruction and 32KB data), ran at 2.2 volts, was manufactured using a 0.25 micrometre process, had 9.3 million transistors, and fit in a Socket 7 or Super7 motherboard.
The K6-2 was designed as a competitor to the slightly older and significantly more expensive Intel Pentium II. Performance of the two chips was broadly similar: the previous K6 tending to be faster for general-purpose computing, the Intel part clearly superior at floating-point tasks. The K6-2 was a very successful chip and provided AMD with the marketing base and the financial stability it would need to introduce the Athlon.
The K6-2 was the first CPU to introduce a floating point SIMD instruction set (dubbed 3DNow by AMD), which could significantly boost the performance of 3D-enabled applications. It beat to the market the similar but more complicated SSE instruction set from Intel, by several months.
Nearly all K6-2 were designed to utilise 100MHz Super7 mainboards, and this provided a major boost to system performance. Early in the K6-2's career, the K6-2 300 was by far the best-selling variant. It rapidly established an excellent reputation in the marketplace and competed fiercely with Intel's Celeron 300A for the non-exotic performance market. The Celeron offered a smaller but faster cache and an excellent floating-point unit; the K6-2 offered much faster RAM access (courtesy of the Super7 mainboard) and 3DNow graphics extensions. Both parts sold well, and both attracted their share of loyalists (at this time, the fastest available Pentium II were slightly more powerful than either of the cheaper chips, but vastly more expensive).
As the market moved on, AMD released a long series of faster K6-2 parts, the best-selling ones being the 350, 400, 450, and 500. By the time the 450 and the 500 were mainstream parts, newer and faster chips had taken the high-performance market and K6-2 still competed with Celerons, but in the budget CPU category. The 100MHz mainboard of the K6-2 allowed it to withstand the effects of ever-increasing CPU multipliers fairly gracefully and in later life it remained surprisingly competitive.
The little-known K6-2+ was an enhanced K6-2 with 128KB of integrated L2 cache and built on a 0.18 micrometre process (essentially, a smaller version of the K6-III+). The K6-2+ was specifically designed as a low-power mobile CPU, and released at a time when mainstream desktop machines were fast moving on to newer platforms like the Athlon. It sold in modest numbers to its target market, and although AMD made no attempt to publicise this, it was also made available as an orthodox desktop CPU. The desktop-packaged K6-2+ was overshadowed in the market by the Athlon and the K6-III (both significantly faster parts) and the original K6-2 which, although slower and only marginally cheaper, was better-known and easier to source compatible motherboards for. The K6-2+ topped out at 570MHz.
Source: Wikipedia, the free encyclopedia.