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Advanced Micro Devices, Inc. (AMD) was founded in 1969 and is the second-largest supplier of IBM PC compatible processors, and a leading supplier of non-volatile flash memory. AMD makes the Athlon and Duron lines of x86-compatible processors. This is not to imply that AMD produces x86-specific components, as their more general components have been found in early Apple computers and numerous other electronic devices.

Table of contents
1 History
2 AMD64
3 See also
4 External link


The company got its start in the microprocessor business in 1979 as a second-source manufacturer of the Intel 8086 and 8088 processors, under contract from Intel. AMD later produced the 80286, or 286, under the same arrangement, but then Intel cancelled the agreement in 1986. AMD then made its own clones of the later Intel 80386 and 80486 models, which were sold at a significantly lower price than the Intel versions.

During this time, AMD attempted to embrace the perceived shift towards RISC with their own AMD 29K processor (based on a bitslice computational model), and they attempted to diversify into graphics and audio devices as well as flash memory. While the AMD 29K survived as an embedded processor and AMD continues to make industry leading flash memory, AMD was not as successful with its other endeavours. AMD decided to switch gears and concentrate solely on Intel compatible microprocessors and flash memory. This put them in direct competition with Intel for x86 compatible processors and their flash memory secondary markets.

Their first completely in-house processor was the K5, launched very belatedly in 1995. The "K" was a reference to the "Kryptonite". Architecturally it had more in common with the newly-released Pentium Pro than the Pentium or Cyrix's 6x86. There were a number of problems however; a confusing naming system was employed, with some chips being represented by their true core speed, others with a PR number. More tellingly the K5 couldn't match the 6x86's Integer performance, nor the Pentium's FPU performance. This, combined with the fact that the design scaled badly, doomed the K5 to near-total failure in the market place. To it's credit though, it didn't suffer from the compatibility problems that the 6x86 did, and didn't run as hot as Cyrix's chip.

In 1996, AMD purchased NexGen, Inc and the rights to intellectual property behind their Nx series of x86 compatible processors. In a year, they reworked the Nx686 microarchitecture (a processor NexGen had a complete design for, but which did not make it to market) to include a feedback dynamic instruction reording mechanism, MMX instructions and made it pin compatible with Intel Pentium, which allowed it to be used in the widely available "Socket 7" based motherboards and branded it the K6. Like the Nx686 and Nx586 before it, the K6 translated the Pentium compatible x86 instruction set to RISC-like micro-instructions. In the following year, AMD released the K6-2 which added floating point multimedia instructions, as well a new socket standard called "Super Socket 7" both of which delivered enhanced performance.

In January 1999, the final iteration of the K6-x series, the 450 MHz K6-III, was extremely competetive with Intel's top of the line chips. This chip was essentially a K6-2 with 256 kilobytes of full-speed level 2 cache integrated into the core and a better branch prediction unit. While it matched (generally beating) the Pentium II/III in Integer operations, the FPU was a non-pipelined serial design and couldn't compete with Intel's more advanced FPU architecture.

Throughout its lifetime, the K6 processor came close, but never quite seemed to equal the performance of processor offerings from Intel. Furthermore, the motherboards that worked with the K6 were of varying quality, and AMD had process manufacturing difficulties which impacted some shipments. As such AMD gained a reputation of making a somewhat slower and less reliable "x86 clone" even though the performance difference was not that much and the best K6 compatible motherboards were very reliable. This forced AMD into a position of selling their K6 processors at a substantial discount versus Intel's P6 core based processors, the Pentium II and the Pentium III. Intel responded to AMD's with the "Celeron" version of their Pentiums which were cheaper and slower in a partially successful attempt to drive AMD out of the market.

In August of 1999, AMD released the Athlon (K7) processor. The Athlon had a very advanced micro-architecture geared towards overall performance. The timing of the release of this processor put it at a great performance advantage versus Intel's P6 core based processors (which culminated as their mainline processor in the Pentium III.) The main reason being that the Intel P6 core was nearing its end of life and was running out of gas, while the Athlon was just getting started. Objectively, the Athlon had higher "per clock" architectural performance versus the comparable Intel P6 core based parts, as well as higher frequencies. AMD announced a 1GHz Athlon in early March 2000 and delivered them in that same month. Intel also announced a 1Ghz Pentium a few days later, but did not ship them in significant volume until June of that year.

AMD also worked hard to increase the reliability and performance of motherboards for the Athlon. They also improved the discipline and predictability of their manufacturing process. AMD also release a second line of processors based on the Athlon core called the Duron which was a slower and cheaper version of the processor aimed at competing against the still shipping Celeron processor, providing some insulation for the Athlon against AMD prior reputation for only making cheaper and slower "Intel clones". The combination of these technical and marketing successes did much to repair and bolster AMD's reputation for making high performance CPUs that shipped and worked very reliably. AMD continued to undercut Intel on price which helped them establish up to 20% marketshare.

In 2001, Intel released the Pentium 4 architecture (codenamed Willamette) which had a radically different microarchitecture than the Athlon or the P6 cores. While sporting a drammatically higher clock rate, the per-clock architectural performance of the Pentium 4 appears to be much slower than the Athlon or even Intel's own P6 core based processors. This created a lot of confusion in the marketplace as customers would be lead to believe that the Pentium 4's had higher performance because of its higher clock rate, though benchmarks would tell a different story.

AMD responded with a new K7 core (codenamed Palomino) which had superior memory prefetching mechanisms and an on-chip L2 cache and also rebranded them based on Model numbers which would approximately project the clock rate relative performance of these new Athlons versus the earliest versions of the Athlon. The net effect of this was for the Model numbers to be more comparable to the Pentium 4's actual clock rate. For AMD processors of a given Model number, the comparable Pentium 4 by corresponding clock rate showed rough parity on performance in a wide variety of benchmarks.

Intel had its revenge against AMD and its Athlon by ramping the Pentium 4 clock rate aggressively in its early lifetime, just as the Athlon was nearing its end of life, giving it a brief period of performance dominance. But by this point, AMD had already gained its reputation as vendor which makes high performing x86 compatible CPUs at competitive prices.


AMD's future strategy appears to be diverging significantly from that of Intel with the release of the 64-bit AMD64 "Hammer" architecture. Whilst retaining support for the traditional x86 instruction set, the Hammer's native 64-bit mode is unique to AMD processors and incompatible with the IA-64 architecture used in Intel's Itanium processor. As a relatively straightforward extension and cleanup of the basic x86 architecture, from a technical perspective AMD's conservative approach looks likely to produce, at least initially, better price-performance than the Itanium and its successors.

This also gives AMD a marketing advantage in that it can leverage its ordinary 32-bit x86 processor market to naturally upgrade and adopt its 64-bit processors without introducing risk to the existing software infrastructure. However, the potential for this processor to compete with Itanium head on in its intended markets (high-end 64 bit servers) remains unclear.

AMD released its first AMD64 processor (K8), the Opteron, in March 2003. The Opteron is designed for workstation and server systems, including those containing more than one processor. However, Cray announced that it was going to use the Opteron as the basis for a top of the line super computer called "Red Storm", indicating that there seemed to be no limit for what sort of applications the Opteron could be used for. AMD then released Athlon 64 and Athlon 64 FX in September 2003 based on the same core architecture, which most benchmarks indicated both as performing equal or better than the Pentium 4. However the Pentium 4 seems to have retained its performance advantage in streaming media processing applications.

The Hammer core is very similar to the Athlon in basic microarchitecture, but includes 3 major differences 1) The inclusion of the AMD64 64-bit instruction set, 2) Including a built in memory controller, 3) The use of the "Hypertransport" point to point bus. There improve both the capabilities and performance of the Hammer versus the Athlon.

See also

External link