The K6-2 is an x86

microprocessor A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circ ...

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! 3DNow! is a deprecated extension to the x86 instruction set developed by Advanced Micro Devices (AMD). It adds single instruction multiple data (SIMD) instructions to the base x86 instruction set, enabling it to perform vector processing of fl ...

SIMD instruction set, featured a larger 64

KiB The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable unit ...

Level 1 cache (32 KiB instruction and 32 KiB data), and an upgraded system-bus interface called Super Socket 7, which was backward compatible with older

Socket 7 Socket 7 is a physical and electrical specification for an x86-style CPU socket on a personal computer motherboard. It was released in June 1995. The socket supersedes the earlier Socket 5, and accepts P5 Pentium microprocessors manufactured by ...

motherboard A motherboard (also called mainboard, main circuit board, mb, mboard, backplane board, base board, system board, logic board (only in Apple computers) or mobo) is the main printed circuit board (PCB) in general-purpose computers and other expand ...

s. It was manufactured using a 0.25

micrometre The micrometre (American and British English spelling differences#-re, -er, international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American and British English spelling differences# ...

process, ran at 2.2

volt The volt (symbol: V) is the unit of electric potential, electric potential difference (voltage), and electromotive force in the International System of Units (SI). It is named after the Italian physicist Alessandro Volta (1745–1827). Defin ...

s, and had 9.3 million

transistor upright=1.4, gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink). A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch ...

History

The K6-2 was designed as a competitor to Intel's flagship processor, the significantly more expensive

Pentium II The Pentium II brand refers to Intel's sixth-generation microarchitecture (" P6") and x86-compatible microprocessors introduced on May 7, 1997. Containing 7.5 million transistors (27.4 million in the case of the mobile Dixon with 256 K ...

. Performance of the two chips was similar: the previous K6 tended to be faster for general-purpose computing, while the Intel part was faster in x87 floating-point applications. To battle the Pentium 2's dominance on floating point calculations the K6-2 was the first CPU to introduce a floating point

SIMD Single instruction, multiple data (SIMD) is a type of parallel processing in Flynn's taxonomy. SIMD can be internal (part of the hardware design) and it can be directly accessible through an instruction set architecture (ISA), but it shoul ...

instruction set (dubbed

by AMD), which significantly boosted performance. However programs needed to be specifically tailored for the new instructions and despite beating Intel's SSE instruction set to market, 3DNow achieved only limited popularity. Super Socket 7, which increased the processor bus from 66 MHz to 100 MHz, allowed the K6-2 to withstand the effects of ever-increasing CPU multipliers fairly gracefully and in later life it remained surprisingly competitive. Nearly all K6-2s were designed to use 100 MHz Super Socket 7 mainboards, allowing the system-bus to keep pace with the K6-2's clock-frequency. The K6-2 was a very financially successful chip and enabled AMD to earn the revenue it would need to introduce the forthcoming

Athlon Athlon is the brand name applied to a series of x86-compatible microprocessors designed and manufactured by Advanced Micro Devices (AMD). The original Athlon (now called Athlon Classic) was the first seventh-generation x86 processor and the fi ...

. The introductory K6-2 300 was by far the best-selling variant. It rapidly established an excellent reputation in the marketplace and offered a favorable price/performance ratio versus Intel's

Celeron Celeron is Intel's brand name for low-end IA-32 and x86-64 computer microprocessor models targeted at low-cost personal computers. Celeron processors are compatible with IA-32 software. They typically offer less performance per clock speed co ...

300A. While the K6-2 had mediocre floating-point performance compared to the Celeron, it offered faster system RAM access (courtesy of the Super 7 mainboard), as well as 3DNow graphics extensions. 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, the K6-2 family had already moved to the budget PC segment, where it still competed successfully against Intel's Celeron.

K6-2+

Despite the name, the little-known K6-2+ was based on the AMD K6-III+ design (model 13) with 128 KiB of integrated L2 cache and built on a 0.18

process (essentially a K6-III+ with half the L2 cache). The K6-2+ was specifically designed as a low-power mobile CPU. Some motherboard companies such as Gigabyte and FIC provided BIOS updates for their desktop motherboards to allow for usage of these processors; for other officially not supported mainboards, the community created unofficial BIOS updates on their own. Most K6-2+ motherboards did not support a clock multiplier setting greater than 5.5 since 550 MHz was the highest official speed of the K6-2+ (100*5.5 = 550) but a little known feature of both the K6-2 and K6-2+ was that it interpreted the motherboard clock multiplier setting 2 as 6. This allowed many users to run their K6-2+ 550 MHz and often even a K6-2+ 500 MHz at a speed of 600 MHz simply by setting the motherboard clock multiplier to 2.

Features

CPU features table

Models

K6-2 (Chomper, 250 nm)

* Package number: 26050 * CPUID: Family 5, Model 8, Stepping 0 * L1-Cache: 32 + 32 KiB (Data + Instructions) *

MMX MMX may refer to: * 2010, in Roman numerals Science and technology * MMX (instruction set), a single-instruction, multiple-data instruction set designed by Intel * MMX Mineração, a Brazilian mining company * Martian Moons eXploration, a Japane ...

* 9.3 million transistors * Super Socket 7 * Front-side bus: 66, 100 MHz * VCore: 2.2V * First release: May 28, 1998 * Manufacturing process: 0.25 μm * Clockrate: 233, 266, 300, 333, 350 & 366 MHz

K6-2 (Chomper Extended (CXT), 250 nm)

* Package number: 26351 * CPUID: Family 5, Model 8, Stepping 12 * L1-Cache: 32 + 32 KiB (Data + Instructions) *

* Super Socket 7 * Front-side bus: 66, 95, 97, 100 MHz * VCore: 2.0(mobile)/2.2/2.3/2.4V * First release: November 16, 1998 * Manufacturing process: 0.25 μm * Clockrate: 200, 233, 266, 300, 333, 350, 366, 380, 400, 427.5, 450, 475, 500, 533 & 550 MHz

References

External links

AMD-K6-2 Processor
AMD (archived version)
Anandtech: Super7 Upgrade Guide

* at Geek.com

Pictures of AMD-K6-2 chips at CPUShack.com
{{AMD processors Computer-related introductions in 1998 K06-2 Superscalar microprocessors