Cyrix

X87 and 487 math coprocessors

The first Cyrix product for the personal computer market was the x86 compatible math coprocessor . It was released in 1989 in two versions - FastMath 83D87 and 83S87. The first of them has become the fastest math co-processor out of 387 compatible, overtaking an analog from Intel by 50%.

In 1992 , the already fully-fledged 486SLC and 486DLC CPUs were released. Despite their name, they were compatible with contacts not with 486, but with 386SX and DX, respectively. They contained a level I cache on a chip and used the instruction set 486, and the average performance was between 386 and 486. Most of them became popular among users who wanted to upgrade 386 computers and among dealers who were able to get 386 motherboards from the processor inexpensive 486.

These products were criticized for lack of performance that does not match the names, and for the confusion of names with the Intel-SL series and IBM -SLC series. Despite this, they found application in very inexpensive PCs and laptops.

Later 486SRX2 and 486DRX2 were released, representing the double-frequency SLC and DLC versions. They were offered exclusively as upgrades from 386 to 486.

Beginning of competition with Intel CPUs

Over time, Cyrix was able to release a 486 processor, which was fully compatible with Intel's contacts. However, AMD managed to get ahead of Cyrix, and, moreover, the processors of the latter showed weaker test results, which focused them exclusively on the segment of cheap computers and upgrades.

In addition, Cyrix was unable to conclude contracts with major assemblers (as they were able to do in AMD with Acer and Compaq ). Cyrix processors could be used to upgrade old motherboards that generated 5 V, instead of 3.3 V (for example, versions at 50, 66, and 80 MHz ).

Attempts to create a competitor Pentium

In 1995, the story was repeated with a new generation of processors. Since the Pentium- tilt was not yet ready, the company released Cx5x86, compatible with pins 486 and designed for frequencies of 100 and 120 MHz, whose performance corresponded to a Pentium at 75 MHz. In addition, the company modestly insisted on a limited emulation of Pentium instructions - applications collected under Pentium are becoming more and more. The 5x86 family did not receive a complete set of instructions, which led to unpredictable program behavior.

6x86 processor release

1995 was marked by the release of the most widely-known model of the processor Cyrix, 6x86 , faster for the first time than its competing counterpart from Intel. The crystal size of the new processor was huge, which made production more expensive and created cooling problems. Initially, a very high sales price was assigned, which had to be reduced due to the poor performance of the mathematical part of the processor compared to competitors. This parameter was unexpectedly important for the emerging three-dimensional games. The processor used the original second-level cache interface: Linear Burst, which was not supported by the Intel chipsets that dominated the market.

Home assemblers almost completely ignored the slow, albeit cheap processor. Cyrix has gained significant recognition in the niche of office computers for business applications collected by small firms at the lowest cost; major computer manufacturers did not use it. The continuation of the series as a 6x86L model was distinguished by reduced supply voltage and, accordingly, lower power consumption, and support for MMX commands in the 6x86MX model (as well as a large amount of level I cache memory in the latter case). Then came the MII, based on the same 6x86 design and received a new name just for the sake of competition with the Pentium II .

MediaGx multimedia processor

A year later, in 1996 , the company created the MediaGX processor, into which it was possible to integrate all the main components of the PC, including support for audio and video output. It was based on the previous 5x86 design and operated at 120 MHz and 133 MHz. The speed was low, for which the chip was criticized more than once, but the low price did the trick: for the first time, the Cyrix product became the basis of a production computer — the low-cost Compaq Presario 2100 and 2100. Such support helped to further supply the Packard Bell processors and proved the consistency of the products. Orders for 6x86 from the same Packard Bell and eMachines followed.

Later versions of MediaGX operated at frequencies up to 333 MHz and had MMX support. An auxiliary chip added support for video output functions.

Due to the greater efficiency of 6x86 when executing each command than that of the Pentium , as well as to take into account its faster bus, the Cyrix (as well as AMD) began to use a specific scale of processor names reflecting their comparative performance with the Pentium.

So, 6x86 with a frequency of 133 MHz was a bit faster than a Pentium 166 MHz, and therefore it got the name P166 +. Intel’s legal pressure to use the P166 and P200 expressions in other products forced Cyrix to add the letter R to this system.

The rating, calculated in this way, was very, very doubtful, because the advantage of Cyrix-chips, seen in ordinary desktop applications, was lost when comparing the mathematical performance, and hence the speed of the latest games. In addition, the low price meant the use of low-cost systems, where other components could have lower speed: hard drives, graphics and sound cards, modems.

AMD applied the PR rating in its K5 processor, then abandoned it and again returned to its use in later products.

While developing and selling its own processors, Cyrix has always relied on third-party companies for their actual production. At the first stage, these were Texas Instruments and SGS-Thomson (now STMicroelectronics ). In 1994, after a series of conflicts with TI and difficulties in production at SGS Thomson, Cyrix turned to IBM , whose production technologies were in no way inferior to Intel.

Under the terms of the agreement, IBM was able to produce and sell processors developed by Cyrix under its own brand. Many perceived this as IBM’s intention to widely use 6x86 in its product line, contributing to strengthening their authority even more, but in reality this did not happen: most IBM computers continued to be equipped with Intel and AMD processors, and Cyrix was used only in a few low-budget series. intended for export. In addition, IBM-made processors began to compete with those that supplied to the market Cyrix, in some cases, even at the expense of lower prices.

Intel vs Cyrix

Unlike AMD, Cyrix has never relied on the licensing of the development of Intel, and all the work on the creation of processors was done within the walls of the company, including the tremendous efforts to accurately recreate Intel technologies. These Cyrix products differed from AMD 386 and 486, which contain part of Intel microcode.

Nevertheless, in an effort to protect itself from competition, Intel for many years led litigation against Cyrix, accusing it of operating proprietary technologies. By and large, this struggle was not crowned with success, and the truce was achieved out of court. Under the terms of the agreement, Cyrix was allowed to manufacture its own processors using any of the companies that already have a license to manufacture Intel-processors.

Thus, the interests of both companies were respected: Cyrix could use the services of Texas Instruments, SGS Thomson and IBM, and Intel avoided the danger of unlimited competitor growth.

Cyrix vs. Intel

However, in 1997 the situation repeated exactly the opposite: now Cyrix accused Intel of violating its patents, in particular, energy management technologies and renaming registers to Pentium Pro and Pentium II

It would seem that there was a long standoff in the courts, but the solution was found very soon: another mutual license agreement. Now both companies received full and free access to each other’s patented technologies. Like the previous agreement, the current one did not eliminate the violation, but allowed Intel to continue production on any technology.

In August 1997, at the same time as ongoing litigation with Intel, Cyrix was merged with National Semiconductor (this company also had an Intel cross-license).

Now Cyrix has additional marketing power, as well as access to National Semiconductor factories , focused on memory and high-speed telecommunications equipment.

Because of the similarity in the technology of production of memory and processors for the new alliance, attractive prospects loomed. And although the agreement with IBM continued to operate, the entire production was gradually transferred to the power of National Semiconductor. As a result of the merger, the financial base of Cyrix and its project resources have been strengthened.

New strategic direction

But besides this, the general direction of the company's development was also affected: in National Semiconductor they preferred to rely on MediaGX class single-chip budget products, rather than powerful 6x86 and MII processors, designed to compete with the Pentium II. Whether this was caused by doubts about the credibility of Cyrix developers or the difficulties of dealing with Intel is not entirely clear. What is certain is that MediaGX, in the absence of direct competitors and the growing demand for inexpensive PCs, looked very promising.

PCI bus issues

However, shortly after the merger with Cyrix, National Semiconductor fell into the financial difficulties, which did not slow down to affect both companies. By early 1999 , AMD and Intel were involved in the race of clock frequencies, speeds reached 450 MHz and higher, while Cyrix took a year to accelerate MII from PR-300 to PR-333. At the same time, in reality neither of them reached the 300 MHz clock frequency. A serious problem was the non-standard frequency of the MII processor bus: 83 MHz. The vast majority of Socket 7 motherboards received a PCI bus frequency by dividing the processor bus frequency into two, as a rule, it turned out to be 30 or 33 MHz. However, for the MII, a very non-standard bus speed of 41.5 MHz came out. Under such conditions, not all devices using the PCI bus could function normally, many failed, some refused altogether. On separate motherboards it was possible to use a 1/3 divider, which gave a frequency of 27.7 MHz. This option was much more stable, but severely limited bandwidth.

We only managed to get rid of these difficulties in the latest versions of the processor, which was capable of supporting the processor bus frequency of 100 MHz.

Unsuccessful competition with Intel and AMD

In the meantime, the pressure of the budget Intel and AMD chips became ever more noticeable. They became cheaper, while maintaining its high performance. The product Cyrix, which was considered in 1996 to be fast, was gradually pushed into the sector of medium and then weak processors, threatening to be completely ousted from the market.

The last processor under the Cyrix brand was the MII-433, which worked at 300 MHz (100x3) and overtook AMD K6 / 2-300 in mathematical operations (measured by Dr. Hardware). He was constantly subjected to comparisons with processors that actually worked at a frequency of 433 MHz, which was, of course, incorrect, but the reason for this was given by the name itself.

Engineers leave company

National Semiconductor did not pursue the goal of strengthening its position in the CPU market, and, left without clear prospects, the engineers left the united company one by one. By the time the National Semiconductor’s Cyrix division was sold to Taiwanese company VIA Technologies, there was no trace of the former strong team, and the demand for MII processors was exhausted. VIA decided to use the acquired name for marking the processor developed by Centaur Technology , since they believed that it was known more widely than Centaur and even VIA.

Takeover by VIA

National Semiconductor, however, retained the rights to the highly integrated MediaGX processor, and continued to market it, renaming it to Geode , and hoping to sell it as an embedded one. In the end, the development was entirely bought by AMD in 2003.

In June 2006, the latter announced the release of the most economical processor, consuming only 0.9 watts of power. Based on the Geode core, it shows that Cyrix’s architectural design is robust.

Despite the short independent existence and the subsequent devaluation of its brand, Cyrix broke the way to the market for low-cost processors, thereby lowering the lower price threshold for computers and forcing Intel to produce an inexpensive alternative - Celeron , and revise the pricing for high-end models.

It is likely that the acquired intellectual property will help VIA successfully repel Intel patent attacks, even though the production of processors under the Cyrix brand has been stopped.

• It was used http://www.redhill.net.au (in English) with the permission of the authors, with abbreviations.

• Cyrix 6x86
• MediaGX
• Cyrix III
• x86

In English. lang

• Identification of Cyrix / TI / IBM / ST CPUs. (unavailable link from 10-08-2013 [2185 days] - history , copy ) Processor names Cyrix, Texas Instruments, IBM, ST.
• Cyrix processors at cpu-collection.de. Cyrix processors on the German site cpu-collection.de
• CPU-INFO: Cyrix, indepth processor history. Detailed history of Cyrix processors
• Coprocessor.info: Cyrix coprocessor development, the company story. The history of the company and its co-processors on the website coprocessor.info
• The secret history of the sub- $ 1,000 computer. (inaccessible link) "Secret" history of cheap computers. News site cnet.com.