Cyrix founder Jerry Rogers aggressively recruited engineers and pushed them, eventually assembling a small but efficient design team of 30 people.
Cyrix merged with National Semiconductor, November 11, 1997.
Its early CPU products included the 486SLC and 486DLC, released in 1992, which, despite their names, were pin-compatible with the 386SX and DX, respectively. While they added an on-chip L1 cache and the 486 instruction set, performance-wise they were somewhere between the 386 and the 486. The chips were mostly used as upgrades by end users looking to improve performance of an aging 386 and especially by dealers, who by changing the CPU could turn slow-selling 386 boards into budget 486 boards. The chips were widely criticized in product reviews for not offering the performance suggested by their names, and for the confusion caused by their naming similarity with Intel's SL line and IBM's SLC line of CPUs, neither of which was related to Cyrix's SLC. The chips did see use in very low-cost PC clones and in laptops.
Cyrix would later release the Cyrix 486SRX2 and 486DRX2, which were essentially clock-doubled versions of the SLC and DLC, marketed exclusively to consumers as 386-to-486 upgrades.
Eventually Cyrix was able to release a 486 that was pin-compatible with its Intel counterparts. However, the chips were later to market than AMD's 486s and benchmarked slightly slower than AMD and Intel counterparts, which relegated them to the budget and upgrade market. While AMD had been able to sell some of its 486s to large OEMs, notably Acer and Compaq, Cyrix had not. The Cyrix chips did gain some following with upgraders, as their 50-, 66- and 80 MHz 486 CPUs ran at 5 volts, rather than the 3.3 volts used by AMD, making the Cyrix chips usable as upgrades in early 486 motherboards.
In 1995, with its Pentium clone not yet ready to ship, Cyrix repeated its own history and released the Cx5x86, which plugged into a 486 socket, ran at 100, 120 or 133 MHz, and yielded performance comparable to that of a Pentium running at 75 MHz. While AMD's Am5x86 was little more than a clock-quadrupled 486 with a new name, Cyrix's 5x86 implemented some Pentium-like features.
Later in 1995 Cyrix released its best-known chip, the 6x86 (M1), this processor continued the Cyrix tradition of making faster replacements for Intel designed sockets, however the 6x86 was the star performer in the range, giving a tangible performance boost over the Intel "equivalent". 6x86 processors were given names such as P166+ indicating a performance better than a Pentium 166MHz processor, in fact the 6x86 processor was clocked at a significantly lower speed than the Pentium part it outperformed. Initially Cyrix tried to charge a premium for its extra performance, but the 6x86's math coprocessor was not as fast as that in the Intel Pentium, the main difference being not one of actual computing performance on the coprocessor, but the lack of instruction pipelining. Due to the increasing popularity of first-person 3D games, Cyrix was forced to lower its prices. While the 6x86 quickly gained a following among computer enthusiasts and independent computer shops, unlike AMD its chips had yet to be used by a major OEM customer.
The later 6x86L was a revised 6x86 that consumed less power, and the 6x86MX (M2) added MMX instructions and a larger L1 cache. The MII, based on the 6x86MX design, was little more than a name change intended to help the chip compete better with the Pentium II.
In 1996 Cyrix released the MediaGX CPU, which integrated all of the major discrete components of a PC, including sound and video, onto one chip. Initially based on the old 5x86 technology and running at 120 or 133 MHz, its performance was widely criticized but its low price made it successful. The MediaGX led to Cyrix's first big win, when Compaq used it in its lowest-priced Presario 2100 and 2200 computer. This led to further MediaGX sales to Packard Bell and also seemed to give Cyrix legitimacy, as 6x86 sales to Packard Bell and eMachines quickly followed.
Later versions of the MediaGX ran at speeds of up to 333 MHz and added MMX support. A second chip was added to extend its video capabilities.
The PR nomenclature was controversial because while Cyrix's chips generally outperformed Intel's when running productivity applications, on a clock-for-clock basis its chips were slower for floating point operations, so the PR system broke down when running the newest games. Additionally, since the 6x86's price encouraged its use in budget systems, performance could drop even further when compared with Pentium systems that were using faster hard drives, video cards, sound cards, and modems.
Although AMD used the PR rating in its early K5 chips, it soon abandoned the PR rating, although it would later use a similar concept in marketing its later CPUs.
As part of the manufacturing agreement between the two companies, IBM received the right to build and sell Cyrix-designed CPUs under the IBM name. While some in the industry speculated this would lead to IBM using 6x86 CPUs extensively in its product line and improve Cyrix's reputation, IBM by and large continued to use Intel CPUs, and to a lesser extent, AMD CPUs, in the majority of its products and only used the Cyrix designs in a few budget models, mostly sold outside of the United States. IBM instead sold its 6x86 chips on the open market, competing directly against Cyrix and sometimes undercutting Cyrix's prices.
By and large, Intel lost the Cyrix case. But the final settlement was out of court: Intel agreed that Cyrix had the right to produce their own x86 designs in any foundry that happened to already hold an Intel license. Both firms gained out of this: Cyrix could carry on having their CPUs made by Texas Instruments, SGS Thomson, or IBM, all holders of Intel cross-licenses; Intel avoided a potentially embarrassing loss.
The follow-on 1997 Cyrix-Intel litigation was the reverse: instead of Intel claiming that Cyrix 486 chips violated their patents, now Cyrix claimed that Intel's Pentium Pro and Pentium II violated Cyrix patents—in particular, power management and register renaming techniques. The case was expected to drag on for years but was settled quite promptly, by another mutual cross-license agreement. Intel and Cyrix now had full and free access to each other's patents. The settlement didn't say whether the Pentium Pro violated Cyrix patents or not; it simply allowed Intel to carry on making them either way—exactly as the previous settlement sidestepped Intel's claim that the Cyrix 486 violated Intel patents.
The merger also resulted in a change of emphasis: National Semiconductor's priority was single-chip budget devices like the MediaGX, rather than higher performance chips like the 6x86 and MII, a revised 6x86 intended to compete more directly with Intel's Pentium II. Whether National Semiconductor doubted Cyrix's ability to produce high-performance chips or feared competing with Intel at the high end of the market is open to debate. The MediaGX, with no direct competition in the marketplace and with continual pressure on OEMs to release lower-cost PCs, looked like the safer bet.
National Semiconductor ran into financial trouble soon after the Cyrix merger, and these problems hurt Cyrix as well. By 1999, AMD and Intel were leapfrogging one another in clock speeds, reaching 450 MHz and beyond while Cyrix took almost a year to push the MII from PR-300 to PR-333. Neither chip actually ran at 300 MHz. A problem suffered by many of the MII models was that they used a non-standard 83 MHz bus. The vast majority of Socket 7 motherboards used a fixed 1/2 divider to clock the PCI bus, normally at 30 MHz or 33 MHz. With the MII's 83 MHz bus, this resulted in the PCI bus running alarmingly out of spec at 41.5 MHz. At this speed, many PCI devices could become unstable or fail to operate. Some motherboards supported a 1/3 divider, which resulted in the PCI bus running at 27.7 MHz. This was more stable, but adversely affected system performance. The problem was only fixed in the final few models, which supported a 100 MHz bus. Almost all of the 6x86 line produced a large amount of heat, and required quite large heatsink/fan combos (for the time) to run properly. There was also a problem which made the 6x86 incompatible with the then-popular SoundBlaster AWE64 sound card. Only 32 of its potential 64 voice polyphony could be utilized, as the WaveSynth/WG software synthesizer relied on a Pentium-specific instruction which the 6x86 lacked. Meanwhile, the MediaGX faced pressure from Intel's and AMD's budget chips, which also continued to get less expensive while offering much greater performance. Cyrix, whose product had been considered a performance product in 1996, had fallen to the mid-range, then the entry level, and to the fringe of the entry level and was in danger of completely losing its market.
The last Cyrix-badged microprocessor was the Cyrix MII-433 which ran at 300 MHz (100x3) and performed faster than an AMD K6/2-300 on FPU calculations (as benched with Dr. Hardware). However, this chip was regularly pitted against actual 433 MHz processors from other manufacturers. Arguably this made the comparison unfair, even though it was directly invited by Cyrix's own marketing.
National Semiconductor distanced itself from the CPU market, and without direction, the Cyrix engineers left one by one. By the time National Semiconductor sold Cyrix to VIA Technologies, the design team was no more and the market for the MII had disappeared. VIA used the Cyrix name on a chip designed by Centaur Technology, since VIA believed Cyrix had better name recognition than Centaur, or possibly even VIA.
National Semiconductor retained the MediaGX design for a few more years, renaming it the Geode and hoping to sell it as an integrated processor. They sold the Geode to AMD in 2003.
In June 2006, AMD unveiled the world's lowest-power x86-compatible processor that consumes only 0.9 watts of power. This processor is based on the Geode core, demonstrating that Cyrix's architectural ingenuity still survives.
Additionally, the acquisition of Cyrix's intellectual property and agreements would be used by VIA to defend itself from its own legal troubles with Intel, even after VIA Technologies stopped using the Cyrix name.
To Cyrix or not to Cyrix. (Cyrix Corp.'s Cx 486DRx2 25/ 50 microprocessor upgrade tested in Compaq DeskPro system) (includes related article on Cyrix's DRx2) (Hardware Review) (Evaluation)
Feb 01, 1994; If you've decided your bleary-eyed 386 needs a little processor caffeine boost, you might throw a glance cyrix's way. The...
Cyrix shakes up Intel: 486 boost to 386SX redefines entry-level. (Cyrix Cx486SLC microprocessor offer low price, high performance)
Jul 01, 1992; cyrix's new Cx486SLC microprocessor is the first microprocessor clone that has really shaken up people and plans at Intel,...