Nigh of y'all are no incertitude familiar with Intel and AMD, Qualcomm, Texas Instruments, and perchance even VIA -- but there's another precursor fleck maker that you should be familiar with. For the better part of a decade, Cyrix brought the world of personal computing to millions in the class of attainable budget PCs, but to exist killed past its all-time product and its inability to run a popular game, followed past a bad merger with a larger partner.

The early 1990s were a strange time for the desktop computing industry. It looked similar Intel was winning despite violent competition in the microprocessor space -- Apple switched to IBM PowerPC, while Motorola'south 68K chips were slowly dragging Commodore'southward Amiga PC to the grave. Arm was merely a tiny flame sparked by Apple and a few others, and was almost entirely focused on developing a processor for the infamous Newton.

This was effectually the same time AMD was liberating its processors from the negative aura of being second-sourced from Intel. Afterwards cloning a few more than generations of Intel CPUs, AMD came up with its own compages, which by the end of the nineties were well regarded in terms of toll and performance.

That success can be attributed at least in office to Cyrix, a company that had a window of opportunity to capture the home PC market and leave both Intel and AMD in the grit, merely ultimately failed to execute and speedily disappeared into the tech graveyard.

Pocket-size Beginnings

Cyrix was founded in 1988 past Jerry Rogers and Tom Brightman, starting out as a manufacturer of high-speed x87 math co-processors for 286 and 386 CPUs. These were some of the greatest minds to leave Texas Instruments and they had high ambitions to take on Intel and crush them at their ain game.

Rogers embarked on an aggressive pursuit to find the best engineers in the US and proceeded to go an infamously hard-driving leader for a team of 30 people that were tasked with the impossible.

The company's beginning math coprocessors outperformed Intel equivalents past ~l% while too being less expensive. This made it possible to pair an AMD 386 CPU and a Cyrix FastMath co-processor and become 486-similar performance at a lower price, which caught the manufacture's attention and encouraged Rogers to take the next step and pursue the CPU market.

In 1992, Cyrix unveiled its first CPUs, the 486SLC and 486DLC, which were intended to compete with Intel'due south 486SX and 486DX. They were also pin-uniform with the 386SX and 386DX, meaning they could exist used as drop-in upgrades on ageing 386 motherboards, and manufacturers were also using them to sell budget laptops.

Both variants offered slightly worse performance that an Intel 486 CPU but significantly ameliorate performance than a 386 CPU. The Cyrix 486 DLC wasn't able to compete with Intel's 486SX offering clock-past-clock, but it was a fully 32-bit scrap and sported 1KB of L1 enshroud, while costing significantly less.

At the fourth dimension, enthusiasts loved the fact that they could use a 486DLC which ran at 33 Mhz to accomplish comparable performance to that of an Intel 486SX running at 25 MHz. That said, it wasn't without problems, every bit information technology could lead to stability issues for some older motherboards that didn't accept extra cache control lines or a CPU register control to enable or disable the on-lath enshroud.

Cyrix also developed a "direct replacement" variant called Cx486DRu2, and subsequently in 1994 released a "clock doubled" version called Cx486DRx2, which had the cache coherency circuitry integrated into the CPU itself.

By and so, however, Intel had released its first Pentium CPU, which drove 486DX2 prices down to the point where the Cyrix alternative had lost its appeal as it was cheaper to upgrade to a 486 motherboard than it was to buy a Cyrix upgrade processor for an quondam 386 motherboard. When the "clock tripled" 486DX4 arrived in 1995, information technology was too little, too late.

Large PC manufacturers such as Acer and Compaq weren't convinced by Cyrix's 486 CPUs and instead opted for AMD'due south 486 processors. This yet didn't end Intel from spending years in court alleging that Cx486 violated its patents, without ever winning a instance.

Cyrix and Intel eventually settled outside of court and the latter agreed that Cyrix had the right to industry its own x86 designs in foundries that happened to hold an Intel cantankerous-license, such as Texas Instruments, IBM, and SGS Thomson (subsequently STMicroelectronics).

Never Repeat the Same Fob Twice… Unless You Are Cyrix

Intel launched the Pentium processor in 1993, based on a new P5 microarchitecture and finally coming up with a marketplace-friendly name. But more than importantly, it raised the bar in terms of performance that ushered in a new era of personal computing. The novel superscalar architecture allowed information technology to complete two instructions per clock, a 64-chip external data motorcoach fabricated it possible to read and write more data on each memory access, the faster floating point unit was capable of upward to 15 times the throughput of the 486 FPU, and several other niceties.

Cyrix took on the challenge to yet once again create a middle ground for Socket 3 motherboards that were non able to handle the new Pentium CPU, before that model was even ready to send. That middle ground was the Cyrix 5x86, which at 75 MHz offered many of the features of fifth-generation processors like the Pentium and AMD's K5.

Cyrix 5x86 CPU with heatsink. Image: NostalgiaNerd

The company fifty-fifty made 100 MHz and 133 MHz versions, but they didn't really accept all the advertised performance-enhancing features since they would cause instability if enabled, and overclocking potential was express. All of these were curt-lived and in six months Cyrix decided to stop selling them and moved on to a different processor design.

Acme Cyrix Through the Lens of Convulse

In 1996, Cyrix unveiled the 6x86 (M1) processor, which was expected to be notwithstanding another drop-in replacement for older Intel CPUs on Socket v and Socket 7 motherboards with decent performance. But this wasn't just an upgrade path for budget systems, information technology was actually a piffling marvel in CPU design that was idea to do the impossible — it combined a RISC cadre with many of the pattern aspects of a CISC one. At the aforementioned time, it continued to use native x86 execution and ordinary microcode, while Intel'due south Pentium Pro and the AMD K5 relied on dynamic translation to micro-operations.

The Cyrix 6x86 was pivot-compatible with the Intel P54C and had six variants with a confusing naming scheme that was supposed to indicate the expected operation level, but wasn't an actual indicator of clock speed.

For instance, the 6x86 PR166+ simply ran at 133 MHz, and was marketed as being equivalent to or better than a Pentium running at 166 MHz, a strategy that AMD would replicate subsequently.

Be that equally information technology may, the problem was that the 6x86 really identified itself as a 486 CPU because it didn't back up the total Intel P5 didactics set. This would quickly become an issue as most application development was slowly migrating towards P5 Pentium-specific optimizations to squeeze more performance using the new instructions. Cyrix somewhen improved compatibility with the Pentium and Pentium Pro through the 6x86MX and 6x86MII variants.

A huge selling point of the 6x86 was that its integer performance was significantly improve than the Pentium'south, which was a skilful advantage to accept at a time when the vast majority of applications and games relied on integer operations. For a while, Cyrix even tried to accuse a premium for that added performance, but eventually that strategy brutal apart.

Cyrix 6x86MX CPU dice shot

As it turned out, the FPU (floating point unit) of the 6x86 was just a slightly modified version of Cyrix's 80387 coprocessor, and every bit such, significantly slower than the new FPU blueprint integrated by Intel's Pentium and Pentium Pro.

To be fair, it was nonetheless anywhere between ii and four times faster than the Intel 80486 FPU, and the Cyrix 6x86 bested the Intel offerings on overall performance. But that whole equation bankrupt down when software developers, particularly those making 3D games, saw the rising popularity of the Pentium and chose to optimize their code in assembly language effectually the advantages of the P5 FPU.

When id Software released Quake in 1996, PC gamers using 6x86 processors discovered they were getting sub-par frame rates that reached at almost, an unplayable 15 frames per 2nd, unless they wanted to drib the resolution down to 320 by 200, in which case you'd have needed a top of the line, Cyrix 6x86MX PR2/200 CPU to get a playable 29.seven frames per 2nd. Meanwhile, gamers with Intel systems had no problem running the game at playable frame rates even at 640 by 480.

John Carmack had figured out that he could overlap integer and floating point operations on Pentium fries, every bit they used different parts of the P5 core for everything except didactics loading. That technique didn't work on the Cyrix core, which exposed the weakness of its FPU. Reviewers at the time plant that in every other benchmark or operation test, the 6x86 CPU would leapfrog the Pentium by xxx to 40 per centum.

Back in the mid 90s, no one knew the verbal direction that computing would take, and Cyrix idea it was best to prioritize integer performance, so information technology produced a processor that lacked instruction pipelining, a feature that would become an essential part of a desktop CPU. Instruction pipelining is a technique that divides tasks into a set of smaller operations that are and then executed by unlike parts of the processor simultaneously, in a more efficient manner. The FPU of the Pentium processor was pipelined, leading to a very depression latency for floating point calculations to handle the graphics of Quake.

The problem was like shooting fish in a barrel to solve and software developers have released patches for their applications and games. Simply id Software had spent besides much time designing Quake around the P5 microarchitecture and never provided such a fix. AMD's K5 and K6 CPUs fared a little better than Cyrix'south, just they were still inferior than Intel'south offerings when it came to Quake, which was a really pop game and a flagship among a new breed of 3D titles.

This had Cyrix CPUs becoming harshly judged on that performance gap, and the company all but lost credibility in the eyes of many enthusiasts. Because the visitor had been unable to score contracts with large PC OEMs, it was a particularly hard blow for Cyrix'south violent customer base that was fabricated upward of those same enthusiasts.

To make matters worse, Cyrix was a fabless chip maker that relied on third parties to manufacture its processors, and those companies used their most advanced lines for their own products. As a effect, Cyrix processors were manufactured on a 600 nm process node while Intel'south were 300 nm.

Efficiency suffered, and this is also why Cyrix CPUs had a reputation for getting extremely hot -- and then much then that enthusiasts were designing hotplates using them as a estrus element. They were overly sensitive to depression-quality ability supplies, and their overclocking potential was as well limited, but that didn't stop people (like this author, whose second PC had a Cyrix 6x86-P166+ CPU inside) from pushing them only a picayune chip and slowly leading them to their demise.

The Fall of the First Truthful Rival to Intel's CPU Hegemony

By 1997, Cyrix had tried everything in their power to forge a partnership with companies like Compaq and HP, as integrating its CPUs into their systems would have generated a steady income stream. It also tried suing Intel for violating its patents on power management and register renaming techniques, but the matter was settled quickly with a mutual cross-license agreement, and then that the two firms could stay focused on producing amend CPUs.

A famous National Semiconductor ad

The litigation took a toll on the already cash-strapped company. Faced with the prospect of bankruptcy, Cyrix agreed to be merged into National Semiconductor. This was seen as a blessing. The company would finally have admission to proper manufacturing plants and a stiff marketing squad that was able to score large contracts. The IBM manufacturing agreements held on for a while, just Cyrix eventually moved all production to National Semiconductor.

Nevertheless equally information technology turns out this motion would seal Cyrix's fate. National Semiconductor wasn't interested in making high performance PC parts, and instead wanted low-power SoCs (system on a chip).

Sure plenty, Cyrix came up with the universally-hated 5x86 MediaGX, a chip that integrated functions like audio, video, and memory controller with a 5x86 core running at 120 or 133 MHz. Information technology was a depression performer, but it managed to convince Compaq to use it in their depression-end Presario computers. This whet other OEM'south appetite for 6x86 CPUs, with Packard Bell and eMachines as notable examples.

The shift in focus didn't stop Cyrix from trying to produce more loftier-performance CPUs, merely it delivered promises and piffling else. National Semiconductor eventually sold Cyrix to Taiwan-based chipset maker VIA Technologies, but by then key people had already left and the MII CPU was an uninteresting part that found no buyers.

The final Cyrix design was the MII-433GP which ran at 300 MHz and, thanks to the unfortunate naming scheme, ended up in comparisons with processors that ran at 433 MHz, which were vastly superior. AMD and Intel were busy racing to i GHz and beyond, and it would take 20 more years for Arm to come along and challenge the two giants in the desktop and server markets -- not to mention totally dominate mobile computing.

VIA put the final smash in the coffin as it used the Cyrix name to supercede "Centaur" branding on processors that actually used an IDT-designed WinChip3 cadre. National Semiconductor kept selling the MediaGX for a few more than years, before rebranding it into Geode and selling the design to AMD in 2003.

Three years later, AMD demonstrated the world'south everyman-power x86-compatible CPU, which took only 0.9 watts of ability and was based on the Geode core, a testament to the ingenuity of the Cyrix design team.

Why Cyrix's Legacy Matters

Whether or not you ever endemic a Cyrix-powered PC, the visitor should be remembered for its legacy and lessons learned. Despite the relatively modest influence on the industry during its decade of beingness, Cyrix's failures proved that improving instructions-per-clock (IPC) was a much more productive attempt for chip makers compared to improving raw clock speeds.

To this day, Intel and AMD have tried to push nominal clock speeds higher with each generation, only after the three GHz milestone, most of the real improvements accept come from rethinking cadre parts of their microarchitectures (and caching). A notable example is AMD'south Zen progression, which has brought single-threaded performance improvements of 68% in less than four years.

Cyrix was able to survive and overcome a lot of legal (and past extension, financial) force per unit area from Intel, who sued almost everyone in the CPU infinite in the 1990s. It showed on two occasions that litigation is detrimental for a good for you market place while cross-licensing deals lead to a lot of cantankerous-pollination between engineering efforts at different companies, which proved beneficial.

Cyrix also operated as a fabless company before that was absurd. These days it's standard do for most silicon giants, including the likes of AMD, Qualcomm, Broadcom, Nvidia, Apple, Marvell, Unigroup Communist china, and HiSilicon, who depend on other companies to industry their chips.

The company's marketing strategy was never great before the National Semiconductor merger, and AMD would repeat the same mistakes with Athlon and Sempron processors in the 2000s. These were labeled equally to betoken that they were faster than an Intel processor, while operating at a lower clock speed, but that didn't e'er translate well in benchmarks or existent-world operation tests. AMD dropped that scheme, merely suffice to say, things remain a bit confusing to this day.

Today, it's unlikely you'll find a Cyrix processor outside of gilded reclaiming operations and enthusiasts' vintage estimator collections. There's some testify online that Cyrix-based desktops were in apply up until at least 2022, significant they lingered for some other decade later on the company had substantially dissolved into VIA Applied science's soup. It'southward unlikely that VIA's Zhaoxin arm nonetheless uses anything coming from the original Cyrix design, merely only time will tell if they learned the lessons to laurels Cyrix's legacy.

Image credit: Cyrix 486 dx2 masthead by Henry Mühlpfordt, Cyrix product boxes past CPU Shack.