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Just wanted an opinion about Socket 7 Processors

C

Chromedome45

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Ok just a question really. Other than the actual Pentium which clocks only up to 233MHz which is the best between a Cyrix and an AMD? I have an AMD K6-II 500 in my newly built Pentium system. Is the Cyrix a match? Just curious :D
 
Unless Cyrix introduced something I don't know about, their best system was 300 MHz. AMD offered more performance. Cyrix had focused on low power designs that included sound and video.
 
Not in my experience.

The K6-2 is pretty darned fast compared to the Cyrix 6x86 MII (the fastest Socket 7 Cyrix that I know of). I've got a couple of SS7 (ASUS P5A boards) that I use with K6-2 CPUs. I've also got a couple of other (Intel...) S7 motherboards with Cyrix CPUs and they don't even compare--it's almost as if they're a generation apart. That K6 outruns some of my P2 boards.
 
Fastest SS7 would be the last batch of K6-3's, nothing Cyrix or Winchip made came close. They had to resort to more cache (K6-3) because the K6-2 line didn't realy speed up much after they got clocked over 450. I have a few Cyrix chips but none installed into a board, to be honest I have a few Pentium systems but the SS7 boards are on the shelf collecting dust.
 
I plan to benchmark all socket 7 CPUs, after I collect the parts that I miss. Will do clock-for-clock comparisons in various frequencies. What I don't have right now is a Winchip 2, a Rise MP6 and an FDIV enabled Pentium. I've got all the rest (unless I missed something). Boards are ASUS P5A (v1.03 and v1.05) and a Shuttle HOT-591P (MVP3 chipset), with the P5A 1.03 being the one I plan to use.
 
So AMD huh! I actually kind of thought so. I have the 500 and a 400 as well. And both run quite quickly. Would like to get a hold of a K6-III 550 if possible.
 
I loved my K6-2 and later K6-3 rigs, those were the days man, great performing systems complete with Voodoo 3 ;-)
 
Cyrix was competitive at first--the 6x86 was faster than the AMD K5 and beat AMD to market--but Cyrix never matched the K6 for performance, let alone the K6-2 line. Cyrix ran out of gas after a couple of years and wasn't able to keep up with AMD and Intel in the megahertz race, and the floating-point performance always lagged too, so people who played 3D games never warmed up to Cyrix, unless they bought one to get started, then swapped the CPU for an AMD later. I did see a few people do that.
 
Cyrix got picked up by National Semiconductor who later sold the name to VIA who used it for Centaur chips while some of Cyrix's chip designs went to AMD as the Geode.
 
Chuck(G) said:
Didn't VIA buy up Cyrix? I thought that Cyrix tried to float a Socket 370 CPU and it just wasn't competitive.
Click to expand...
Yes VIA purchased Cyrix just as they were developing Joshua for the 370 socket.

Because the AMD K5 was such a lemon.. AMD bought NexGen (mainly for their development team) and got them to design the K6..
If they hadnt of purchased NexGen then the story of AMD would of probably been very different
 
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Chromedome45 said:
So AMD huh! I actually kind of thought so. I have the 500 and a 400 as well. And both run quite quickly. Would like to get a hold of a K6-III 550 if possible.
Click to expand...

The K6-III tops at 450 MHz and it is not very overclockable. I can't even get it to 550 MHz, all it does is 500 MHz. The mobile version of K6-III+ 400MHz, with 1.6 stock vcore is more promising, doing 600 MHz with 2-2.4 Volts. Maybe even more. But I can't clock it at 720 MHz (120x6), at least not the one I have. The problem with the mobile CPUs is that the ASUS P5A doesn't properly work with them if it is version 1.05 or 1.06.
 
I remember driving 2 hours both ways to hit a computer show specifically to purchase a K6-2 450mhz OEM proc for a build back when I was a young lad in college *hobbles to the chair with a cane and sits down painfully*

Kidding aside, the K6-2 450 was quite fast for its time, and the K6-2 line is what put AMD on the map, giving them the momentum to follow up with their Athlon lines that just blew Intel out of the water. For about a year, anyway. Still have that system - like Chuck, mine's been running in a rock-solid Asus board since day one (though mine was the P5A-B rather than the P5A). I remember a buddy of mine being SOOOO jealous over my build - he'd just put together a K6-2 300 system the month before, and I got my proc from the computer show for half of the price of his.
 
Wow, no love for the Cyrix here. :D

The 6x86MX / M-II easily outperformed the K6-2 per-clock in pure integer code, but the problem was that it was very hot running and didn't like to clock as high as the K6-2. (Remember the K6-2's were rated at actual clockspeeds instead of a phonus-balonus PR rating like the Cyrix's.) The K6-2 simply ran at speeds far out of the Cyrix's reach, and did so at much lower temperatures, so K6-2 left Cyrix utterly behind. Also, the K6-2 beat it in floating point performance even at lower clockspeeds, even without 3DNow enabled.

Interestingly the original non-3DNow K6 actually has slightly superior DOS efficiency to the K6-2. I ran some DOS benchmarks and it showed that my K6 ran just a hair faster in integer than a similarly-clocked K6-2.

K6-2's make for very nice underclockers and undervolters. I had one running on 2.0v at 200MHz, perfectly stable and running so cool it was happy with just a fairly large heatsink. The Cyrix's also underclock well but they still tend to run quite warm even undervolted.
 
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I thought K5 wasn't THAT bad, it was just *really* late and couldn't clock scale worth a darn. I remember being surprised when I saw it run the old DOS game Dark Ages without the use of a speed throttling utility. :p

(On most post-486 chips the game dies with a 'Divide Error' upon startup. That game is REALLY speed sensitive.)
 
K5's were later to the market and while they were faster then Intel at the same clock speed AMD could not get the speed bumps needed to compete fast enough. My first AMD after the 486-133 was a K5-133 and it was cheap (being dumped at the time), I got it for a work PC not for gaming.
 
Maverick1978 said:
I remember driving 2 hours both ways to hit a computer show specifically to purchase a K6-2 450mhz OEM proc for a build back when I was a young lad in college *hobbles to the chair with a cane and sits down painfully*

Kidding aside, the K6-2 450 was quite fast for its time, and the K6-2 line is what put AMD on the map, giving them the momentum to follow up with their Athlon lines that just blew Intel out of the water. For about a year, anyway. Still have that system - like Chuck, mine's been running in a rock-solid Asus board since day one (though mine was the P5A-B rather than the P5A). I remember a buddy of mine being SOOOO jealous over my build - he'd just put together a K6-2 300 system the month before, and I got my proc from the computer show for half of the price of his.
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The K6-2 quite fast for it's time? You and your buddy were comparing AMD to AMD systems. I had a rather different situation with a buddy of mine. I was a classical AMD fellow and believed that it always had more value for money than Intel. So, with the Athlon available but out of my budget at the time, I went on and purchased a K6-2/550 MHz (the K6-3/450 was at the same price and was a better choice, but I was more impressed by the 550 number, another poor choice). I also got an impressive sounding 32MB S3 Savage 4 card. My buddy followed the local storekeepers advice and went Intel instead with a Mendocino Celeron 433 and chose to ignore the impressive looking 32MB RAM of the Savage 4 and go for the 16MB RIVA TNT2 M64 instead. I though I had the better system, but when I went on to benchmark his, it was blowing mine away big time. So big that you didn't even need to run the benchmarks, even a 5 year old could tell, especially in gaming.
 
If we're talking overclocking, you can remove the cap off of the K6-2/3 CPUs for a more direct fit with the heatsink.

If we're talking about overclocking and the Celerons of the time, they were a way better buy. I OCed a Celeron 400 to 600 and all it took was changing the FSB from 66 to 100MHz. It got crazy hot though it still worked and would have been great with a better cooler. I was an AMD fanboy during that time but if I had to build one of the systems again it would probably be a Celeron with a funky peltier setup unless I could find a Super Socket 7 AT motherboard to stick in a retro case.
 
The top CPUs for the Super Socket 7 platform are the 180nm AMD K6-2+ and K6-3+. Both have on-chip L2 cache (128KB for the K6-2+ and 256KB for the K6-3+). They feature PowerNow which has the benefit of being able to manipulate the multiplier. Under DOS via a driver loaded in CONFIG.SYS and under Windows through an application. These chips work with most late Super Socket 7 boards. I have a boards from Gigabyte, Iwill and AOpen and all they needed was the final BIOS update.

My interest in Super Socket 7 is for Retro DOS Gaming Time-Machine projects. Meaning the combination of old and modern parts to be able to play old DOS Games. From my experiences Super Socket 7 is the way to go for such projects. But apart from that you are better off with a Slot or S370 system to be honest.

Here are some general benchmark results of Socket 7 CPUs:

http://img708.imageshack.us/img708/8820/3dbenchdatabase.png

As part of my projects I also looked into performance with L1 and L2 Cache disabled. The main, and most compatible, method for getting speed sensitive 386 and 486-era games to run. It showed me that under such conditions the AMD is the slowest, closely followed by the plain Pentium. The Cyrix is faster, but the Pentium MMX is the fastest. So depending on what speed you want to target the choice of CPU is quite important for time-machine style projects.

I recommend the plain Pentium. It also allows use of the 1.5 multi which other chips often interpret as 3x. Meaning you can clock it at 100 MHz which avoids issues with many games that can cause difficulties at 133 or 166.

http://img560.imageshack.us/img560/6906/timemachinefsbscaling.png
 
Eep386 said:
Wow, no love for the Cyrix here. :D
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I upgraded from a Pentium-75 to a 6x86L in 1996 or so, and bought a 6x86MX in 1999, which I used until I could upgrade to a K6-2. The Cyrix chips were great for running integer-heavy apps, and much more cost-effective than anything else available at the time. I may have only paid $40 for the 6x86MX--it was a very, very inexpensive chip. At my first job, when times were tough and we had a lot of people forced to run Windows 95 and Office 97 on 50 MHz 486s, I built a lot of Cyrix-based systems on the cheap to help those poor souls out, to get them something that would run Win95 and Office 97 effectively. I'd pick up an Asus motherboard and whatever Cyrix CPU we could afford, along with the cheapest PCI video card I could find, then recycle the 72-pin memory and hard drive from their 486. It wasn't optimal, but it let people spend a lot less time staring at an hourglass.

But once mainstream CPUs hit 350-400 MHz or so, Cyrix couldn't manage to keep up. I'm not sure what the problem was. AMD and Intel pulled away, and I upgraded the 6x86MX to a K6-2, and bought a Slot 1 Celeron-based system to learn Linux on. The Mendocino-architecture Celerons were a very good value for the money at the time.

I hung in there with Cyrix as long as I could, and was sorry to see them fade away. Cyrix seemed to plateau before Natsemi bought them, and Natsemi didn't do anything to break the slump. VIA bought both Cyrix and the Winchip from IDT, merged the teams, but the "VIA Cyrix" branded chips were actually a Winchip design.

I used a few Winchips in my day too, because they were direct replacements for pre-MMX Pentiums. I think I could put them in systems that topped out at 133 MHz, set the multiplier to 1.5, which it used for a 3.5 or 4.0 multiplier, and get something higher than 200 MHz. They were like a Pentium Overdrive chip, but they cost half what the Intel chips would have, and they were fabulous for running productivity apps. They weren't good for games, but since we were using them in an office environment, we considered that a feature. :) The integer performance of a Winchip was pretty close, clock-for-clock, with an Intel Pentium, as I recall.
 
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