Cryix 133 mhz

reaper7534!

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Did anyone ever have one of these ? I ( upgraded ) from a AMD DX4 100 mhz and it felt like I went backwards, what a miserable piece of hardware. I do believe it dropped straight into my motherboad though, maybe.
 
It would have dropped right in if you had a socket 7 board (I don't think you needed a super socket 7, but who knows..).

I have one here. I have all the variations of Cyrix processors. I went through a collecting phase.
 
My dad had a Cyrix 133 for a while, and a 233 ran our home server up until about the time I graduated high school in 2007
 
I had a Cyrix 6x86 P166+ and it was GREAT for anything but gaming. Productivity was great. I later pulled it out and replaced it with a Pentium 90Mhz that was better at gaming even though the Cyrix was technically 133MHz.

My understanding is the FPU on the Cryix CPUs was just a poor implementation and therefore games suffered.
 
It would have dropped right in if you had a socket 7 board (I don't think you needed a super socket 7, but who knows..)

You'd need a Super Socket 7 board for several Cyrix CPUs that used weird bus speeds like 75 and 83 MHz which normal Socket 7 boards usually didn't have support for. Those CPUs were a PITA to get working properly because motherboards at the time usually cascaded the various bus clocks from the CPU FSB. PCI was usually CPUClk/2 so a 75 MHz bus got you 37.5 which was pretty high but generally worked. 83 MHz got you 41.5 and most PCI cards would either not function or overheat and misbehave. AGP and RAM was worse, often being run at the same speed at the FSB and AGP cards didn't at all tolerate 75 or 83 MHz clocks.

The computer tech lab when I was in high school had one machine with a Cyrix MII-333gp. It had an 83 MHz bus and ran at 250 MHz. It was slower than the Pentium 166-200 machines, ran far hotter and was VERY unstable due to the weird bus speeds. We had to install PC-100 memory to keep it from crashing every few minutes. But even then, it was still unstable. We could almost hear the motherboard crying out in pain.

My understanding is the FPU on the Cryix CPUs was just a poor implementation and therefore games suffered.

When Cyrix was designing their 686 class processors, they made the fatal error to concentrate more of the CPUs resources towards integer math and more or less used the FPU from their 486 with few changes. They were blindsided by the explosion in popularity of 3D games like Quake which was the start of their downfall. Their 686 class processors were indeed very good at integer math (hence the PR scheme) but the market moved to software with increasing reliance on a strong FPU, something which Cyrix sorely lacked.
 
You'd need a Super Socket 7 board for several Cyrix CPUs that used weird bus speeds like 75 and 83 MHz which normal Socket 7 boards usually didn't have support for. Those CPUs were a PITA to get working properly because motherboards at the time usually cascaded the various bus clocks from the CPU FSB. PCI was usually CPUClk/2 so a 75 MHz bus got you 37.5 which was pretty high but generally worked. 83 MHz got you 41.5 and most PCI cards would either not function or overheat and misbehave. AGP and RAM was worse, often being run at the same speed at the FSB and AGP cards didn't at all tolerate 75 or 83 MHz clocks.

The computer tech lab when I was in high school had one machine with a Cyrix MII-333gp. It had an 83 MHz bus and ran at 250 MHz. It was slower than the Pentium 166-200 machines, ran far hotter and was VERY unstable due to the weird bus speeds. We had to install PC-100 memory to keep it from crashing every few minutes. But even then, it was still unstable. We could almost hear the motherboard crying out in pain.



When Cyrix was designing their 686 class processors, they made the fatal error to concentrate more of the CPUs resources towards integer math and more or less used the FPU from their 486 with few changes. They were blindsided by the explosion in popularity of 3D games like Quake which was the start of their downfall. Their 686 class processors were indeed very good at integer math (hence the PR scheme) but the market moved to software with increasing reliance on a strong FPU, something which Cyrix sorely lacked.

I'll need to take a peak at Tyan SS7 board I have in one of my retro PC's... I'm almost positive I have like 4 or 5 bus speed options via jumpers.
 
On "fancy" boards, you usually had 60, 66, 75, 83, 100 and sometimes like 102, 107 and 112 for overclocking.

I have two FIC PA-2013 boards which supports all of those bus speeds and up to a 5.5 multiplier. One of them though is an earlier revision which has a bugged VIA chipset which gets unstable over 450 MHz.
 
I had a Cyrix 6x86 P166+ and it was GREAT for anything but gaming. Productivity was great. I later pulled it out and replaced it with a Pentium 90Mhz that was better at gaming even though the Cyrix was technically 133MHz.

My understanding is the FPU on the Cryix CPUs was just a poor implementation and therefore games suffered.

Ditto. I was building a lot of systems in the 90's and the Cyrix/IBM 6x86's were dirt cheap and plenty fast for windows. But they had the world's worst FPU which made most games just crawl. I mean a p90 I had just whooped these things playing games like Wing Commander, Xwing v Tie Fighter, etc. The AMD K6 was a little better, but still not as good as Intel of the time.

This all changes later when 3D cards become mainstream, but back then it was all CPU horsepower that got gaming done.

On "fancy" boards, you usually had 60, 66, 75, 83, 100 and sometimes like 102, 107 and 112 for overclocking.

I have two FIC PA-2013 boards which supports all of those bus speeds and up to a 5.5 multiplier. One of them though is an earlier revision which has a bugged VIA chipset which gets unstable over 450 MHz.

Yeah, with JUMPER pins. I can't remember the last time I've seen those except for the front panel hookups on modern mobos.

edit - oh well CMOS jumper too I guess is about it nowadays
 
I had a Cyrix 6x86 P166+ and it was GREAT for anything but gaming. Productivity was great. I later pulled it out and replaced it with a Pentium 90Mhz that was better at gaming even though the Cyrix was technically 133MHz.

My understanding is the FPU on the Cryix CPUs was just a poor implementation and therefore games suffered.

Same experience here too.

I had an IBM branded Cyrix 6x86L PR166+ (133mhz) and I had a friend with a Pentium 75 that would games at nearly the same or better FPS than mine. Overclocked like shit too IIRC.

I miss those early days :(

Me and that same friend built two new computers at the same time after those. He went with a AMD K6-2 450, and I went with a Celeron 433 on a 440BX. I ended up being able to crank my Celeron 433 up to 590 without a problem, and his K6-2 was never quite that stable.

That started my very long run with the 440BX chipset. Went from that Celeron 433@590, to a Celeron (Coppermine) 600@1035, then to a Celeron (Tualatin) [email protected].
 
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Overclocked like shit too IIRC.

One reason Cyrix resorted to PR schemes is because they had a terrible time ramping up the clocks on their 6x86 architecture. The parts they binned for retail were often at the knife edge of working and not, hence overclocking generally didn't go well.

IBM was aware of this and Cyrix parts sold under their moniker were generally more conservatively rated.
 
One reason Cyrix resorted to PR schemes is because they had a terrible time ramping up the clocks on their 6x86 architecture. The parts they binned for retail were often at the knife edge of working and not, hence overclocking generally didn't go well.

IBM was aware of this and Cyrix parts sold under their moniker were generally more conservatively rated.

Yeah, definitely true. I had good times with my 6x86 PR200+; lousy as it was for Quake and FPU-flogging games, that 150 MHz chip was really terrific for all my other DOS titles. And it was in a rock-solid Gigabyte Super7 motherboard that withstood all its bus speed weirdness without skipping a beat.

All of that said, upgrading to an Athlon 500 was mind-numbing...
 
Same experience here too.

I had an IBM branded Cyrix 6x86L PR166+ (133mhz) and I had a friend with a Pentium 75 that would games at nearly the same or better FPS than mine. Overclocked like shit too IIRC.

I miss those early days :(

Me and that same friend built two new computers at the same time after those. He went with a AMD K6-2 450, and I went with a Celeron 433 on a 440BX. I ended up being able to crank my Celeron 433 up to 590 without a problem, and his K6-2 was never quite that stable.

That started my very long run with the 440BX chipset. Went from that Celeron 433@590, to a Celeron (Coppermine) 600@1035, then to a Celeron (Tualatin) [email protected].

Funny, I too went Celeron after my Cyrix days. But if my memory serves, it was a 440LX chipset for me.
 
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Kinda wish I still had a Cyrix to play with. I have a couple drawers of vintage CPUs, but no Cyrix.
 
Kinda wish I still had a Cyrix to play with. I have a couple drawers of vintage CPUs, but no Cyrix.

I finally decided to try to upgrade past 440BX and switched to a board with an i815 chipset. I had read they only supported 512MB of RAM and assumed that it must just be a soft-limit and that you could run more if you had it. That board/chipset was indeed limited to 512MB of RAM...

I very quickly went back to a 440BX motherboard as soon as I figured out how to run Tualatin based Pentium 3's/Celerons on them.
 
The computer tech lab when I was in high school had one machine with a Cyrix MII-333gp. It had an 83 MHz bus and ran at 250 MHz. It was slower than the Pentium 166-200 machines, ran far hotter and was VERY unstable due to the weird bus speeds. We had to install PC-100 memory to keep it from crashing every few minutes. But even then, it was still unstable. We could almost hear the motherboard crying out in pain.


When Cyrix was designing their 686 class processors, they made the fatal error to concentrate more of the CPUs resources towards integer math and more or less used the FPU from their 486 with few changes. They were blindsided by the explosion in popularity of 3D games like Quake which was the start of their downfall. Their 686 class processors were indeed very good at integer math (hence the PR scheme) but the market moved to software with increasing reliance on a strong FPU, something which Cyrix sorely lacked.
Cyrix made choices that were sensible from a standpoint prior to the explosion of 3D graphics. Their integer performance was quite good per-clock - for any DOS titles short of Quake a Cyrix M1/6x86 was a really defensible choice - but as you say, the FPU was not much better than a 486’s. The MII/6x86MX was underrated for a lot of day to day tasks, but the FPU (and consequently the MMX performance) was still weak, and their clock speeds didn’t scale well. That last problem was really what buried them - resorting to frontside bus trickery jacked the stability of every PCI device connected to the processor, and poisoned their reputation for reliability.

Incidentally, I’m not sure their weak FPU was what ruined them. Intel making a committed effort to stamping out low-end competitors and leaning on their cash supplies and contracts with OEMs to squeeze out Cyrix was probably more damaging than id’s entire software catalog.
 
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I finally decided to try to upgrade past 440BX and switched to a board with an i815 chipset. I had read they only supported 512MB of RAM and assumed that it must just be a soft-limit and that you could run more if you had it. That board/chipset was indeed limited to 512MB of RAM...

I very quickly went back to a 440BX motherboard as soon as I figured out how to run Tualatin based Pentium 3's/Celerons on them.

Yeah I found that out back in 1999, you can not use more than 512 on a 815 board. Although to be fair, back then the average computer had 32-64 Mb of memory and windows 98 wouldnt really use more than 128Mb without tweaking it. The 440BX is a good chipset though, have several old boards, and they are still pretty much bulletproof.
 
Are we talking about the 5x86 133MHz or the 6x86 PR133+? The former used 486 era motherboards and the later, socket 7, not super 7 motherboards. The Super 7's were for M2's and K6's K6 II's etc. You could run those older CPU's on Super 7 motherboards, but the latter came out for newer CPU's designed to compete with Pentium II's.
 
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I had read they only supported 512MB of RAM and assumed that it must just be a soft-limit and that you could run more if you had it.

Yeah, the 512 MB limit was most definitely a hard limit set in the chipset. Intel motherboards usually never had more than two memory slots, but some third party boards had 3-4 slots and you could install more than 512 MB. The BIOS would recognize the extra memory, but it'd say only 512MB was usable. I'm fairly certain the 512 MB limit on i810/i815 chipsets was a direct result from the Xeon line being introduced and Intel wanted to be assholes with market segmentation to force people to buy their more expensive server motherboards and Xeon processors if they wanted more memory. Third party chipsets were a saving grace though, as they didn't usually really care what kind of memory you had installed, as long as it looked like memory.

One really good chipset was the VIA Apollo Pro 266T. It was built to support basically every CPU that existed at the time, both Intel and AMD and was used on quite a few boards. It also supported SMP and was used in some server boards. I have a SuperMicro P3TDDE with the chipset and dual 1.4 GHz Tualatins. It even has a 4x universal AGP slot that will work with basically every AGP card to have ever existed.


and their clock speeds didn’t scale well. That last problem was really what buried them - resorting to frontside bus trickery jacked the stability of every PCI device connected to the processor, and poisoned their reputation for reliability.

Their entire range of processor features tanked their reputation. The PR scheme where they rated their lower clocked parts against higher clocked competitors was one thing, but the weird bus speeds that caused instability was another. And the icing on the cake was that some of their CPUs were promised to have certain features at launch like prefetching and branch prediction that were disabled in final silicon because of severe bugs that caused the CPU to be unstable. There's a whole thread dedicated to unlocking processor features on Cyrix CPUs over on Vogons, and determining which mask revisions are more likely to work with certain features than others.

Incidentally, I’m not sure their weak FPU was what ruined them. Intel making a committed effort to stamping out low-end competitors and leaning on their cash supplies and contracts with OEMs to squeeze out Cyrix was probably more damaging than id’s entire software catalog.

Even though Cyrix had a myriad of troubles, problems with their CPUs wasn't the chief factor that tanked them. They were tied up in court with Intel for years, and had to spend millions of dollars in legal bills on that. Even though they eventually won, the resource expenditure collapsed the company, which is when NSC bought them. NSC sealed their fate by gutting the company and providing no real direction for the engineering team, so they all left. NSC didn't want to spend any money on the Cyrix III, which was actually a promising design, and instead opted to use the Cyrix name with a CentaurHauls design of IDT Winchip fame to make the unrelated C3 processor.

Ironically, the Cyrix core lived on long after Cyrix company folded. NSC sold their Geode to AMD, which was based on Cyrix's 5x86, a cut down 6x86 core. AMD continued to do some refinement to the Geode to make the GX and LX series and sold them up to 2019.
 
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PR90 and a PR200 at various times. Not... good chips. Not good at all. That FPU performance was horrible. Good enough for office work though!
 
I had a Cyrix 6x86 P166+ and it was GREAT for anything but gaming. Productivity was great. I later pulled it out and replaced it with a Pentium 90Mhz that was better at gaming even though the Cyrix was technically 133MHz.

My understanding is the FPU on the Cryix CPUs was just a poor implementation and therefore games suffered.
I had that CPU back in the day as well. I was doing some some Lightwave 3D renders and tested the same scene on my brothers Pentium 100 and the Pentium was nearly twice iirc.
I sold the Cyrix setup the next day to a friend and built a Pentium based setup, just can't remember what chip I went with it at the time.
 
PR90 and a PR200 at various times. Not... good chips. Not good at all. That FPU performance was horrible. Good enough for office work though!
The integer performance for the 6x86 chips was really solid at the price point. If all you cared about were Doom clones and the odd bout of Descent or Duke Nukem 3D, or relatively undemanding DOS platformer and adventure games, they were extremely competitive at the price point while giving you access to Socket7/Super7's advantages over 486es. Unfortunately the FPU was not Pentium-competitive. That shortfall extended to the 6x86MX/MII's as well - even a pretty high-clocked one was never going to do a good job at handling Quake III Arena, though you could stuff it full of RAM and set up a pretty capable dedicated server. The most nettlesome thing about the 6x86 was that it wasn't fully i586 instruction-compatible, which led to edge cases where an application could bomb out. The MII fixed that issue. Unfortunately at that point the arms race between Intel and AMD started heating up, and the MII couldn't compete against the K6 family at a price point conducive to Cyrix's survival. But I really didn't hate 'em.
 
The integer performance for the 6x86 chips was really solid at the price point. If all you cared about were Doom clones and the odd bout of Descent or Duke Nukem 3D, or relatively undemanding DOS platformer and adventure games, they were extremely competitive at the price point while giving you access to Socket7/Super7's advantages over 486es. Unfortunately the FPU was not Pentium-competitive. That shortfall extended to the 6x86MX/MII's as well - even a pretty high-clocked one was never going to do a good job at handling Quake III Arena, though you could stuff it full of RAM and set up a pretty capable dedicated server. The most nettlesome thing about the 6x86 was that it wasn't fully i586 instruction-compatible, which led to edge cases where an application could bomb out. The MII fixed that issue. Unfortunately at that point the arms race between Intel and AMD started heating up, and the MII couldn't compete against the K6 family at a price point conducive to Cyrix's survival. But I really didn't hate 'em.
Oh I didn't hate htem. IT was just annoying - and the oddities with compatibility and DMA mode were a nightmare. Put my first 3d accelerator into one of them - the PR200 in fact - and had to disable DMA mode on some of the Rendition games. Ah well.
 
The only problem I ever had with Cyrix CPU's were the one or two random pieces of software that wouldn't run at all and the poor performance in any games that utilized the FPU. Quake and Quake engine games being the primary problem.
 
I had a Cyrix 133 in a laptop, I want to say an Epson. It played Civ 2 ok as long as you didn't have more than 15 units -- after that, slide show.

I can still hear the constant clicking of the HDD from that machine. I swear you could hear it two rooms away. I sold it to my buddy who stored his master thesis draft on it (backing up to a Zip Drive), then his apartment burnt down -- total catastrophe, two years of work gone.
 
I have owned many a Cyrix back in the day starting with a 486SLC, which was really a 386 pretending to be a 486. It was absolutely pathetic at games, x-wing and tie fighter were barely playable. An intel 486dx/33 just kicked it in the teeth. There have been many more up into the 6x86 era, but ultimately all led to disappointment. The AMD K6 was slightly better, the k6-2 with 3d now was vastly better IF your app supported it (Q3A did but not sure what else). I think I have been thru every brand of cpu at this point.
 
I had a AMD K6-2. Loved that thing when games supported 3DNow!... unfortunately not many did.
 
I found a pr200 a few years back in the company recycling bin bit i dont have a system to put it in.

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I used to have up until recently a socket 7 P133...I think I only tossed it a couple years ago. That thing was a beast in its day. Had a plextor SCSI drive and an awe32.

I remember the 6x86 articles in PCmag. I rmemeber getting PCmag and reading it cover to cover. Then checking out the ads for the parts...those were the days.
 
Did anyone ever have one of these ? I ( upgraded ) from a AMD DX4 100 mhz and it felt like I went backwards, what a miserable piece of hardware. I do believe it dropped straight into my motherboad though, maybe.
yeah, circa 1999 i think, eventually swapped out for the AMD K7-500 Slot A on an Abit PC100 mobo i think
 
I had a Cyrix 6x86 P166+ and it was GREAT for anything but gaming. Productivity was great. I later pulled it out and replaced it with a Pentium 90Mhz that was better at gaming even though the Cyrix was technically 133MHz.

My understanding is the FPU on the Cryix CPUs was just a poor implementation and therefore games suffered.

I was great for gaming until Quake dropped.
 
I was great for gaming until Quake dropped.
It was honestly fine for everything but Quake, and with a Voodoo1 and 64MB RAM my PR200+ tided me over until I upgraded to an Athlon 500 with a Voodoo3 two years later. Now that was a memorable upgrade...
 
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