kixs wrote on 2021-12-08, 11:04:

These cpus aren't multiplier locked. Usually you run them at 100 base clock (95 or 105 is quite ok too) with multi up to 6X.

Yeah, but on a board like the Asus P5A, it would be a real shame to stick with FSB100, since the speed boost when going above 100MHz can be quite substantial.
My fastest SS7 build with an Asus P5A rev 1.04 (a board which I actually bought from you - thank you for that, btw 😁) is running an AMD K6-3+ 400 @ 633 MHz (FSB115 x 5.5 multi) + a GeForce 2 GTS.
This thing is both FAST (for a SS7) and extremely stable! I can play games on it that I never even dreamt of playing 20 years ago on my K6-2 500. Even Return to Castle Wolfenstein is decently playable on it, usually running @ 40+ FPS (with some dips to 10 - 15 FPS in busy scenes) - this would've been a VERY playable performance for me back in the day. 😀

Nice 😀 What voltage does the cpu need at 633?

I haven't played much with SS7 and K6+ CPUs... I've tested FSB speeds a few years ago and if I remember correctly, at least that particular board, wasn't stable above 110Mhz - could be an early revision or some other brand. So everything I test now, it's around 100Mhz FSB - but for testing CPUs it's good enough 😉 Don't know when or if ever I will put together a complete K6+ system for actually playing games on 🤣

H3nrik V! wrote on 2021-12-08, 10:57:

dionb wrote on 2021-12-08, 08:25:

I bought my K63+-500 from eBay for EUR 15 from a seller with hundreds three years ago. Of course, even then they sold out pretty quickly at that price. CPU is legit, and happily works at 600MHz and beyond, although it requires significant extra voltage to be stable at higher clocks. That's on a 1.04 rev Asus P5A btw, that itself is stable up to 133MHz. Got very lucky there 😉

So 4.5x133? Sounds pretty nice 😀

Yep, that was pretty nice. Did need to bump to to 2.1V for that though.

There was an ebay auction with 50 pcs. K6-III+/550ACRs NOS in factory box in Dec. 2020.
Thought about bidding...was sold for 3570 EUROs. Unfortunately I didn't make screenshots.
Now they seem to sell well for 250-300 EUR each.

Recently bought two K6-III+/400ATZ for ~45 EURO each. They run well at stock voltage with 500 MHz which is my current board's max speed and at a very low wattage since they are embedded low power parts with 1.6V.
Who needs a K6-III+/550ACR 🙄

bloodem wrote on 2021-12-08, 11:49:

Yeah, but on a board like the Asus P5A, it would be a real shame to stick with FSB100, since the speed boost when going above 100MHz can be quite substantial.
My fastest SS7 build with an Asus P5A rev 1.04 (a board which I actually bought from you - thank you for that, btw 😁) is running an AMD K6-3+ 400 @ 633 MHz (FSB115 x 5.5 multi) + a GeForce 2 GTS.
This thing is both FAST (for a SS7) and extremely stable! I can play games on it that I never even dreamt of playing 20 years ago on my K6-2 500. Even Return to Castle Wolfenstein is decently playable on it, usually running @ 40+ FPS (with some dips to 10 - 15 FPS in busy scenes) - this would've been a VERY playable performance for me back in the day. 😀

I did play RCTW on my slower K6-3 with GF2 when it came out. It was 30 FPS, with dips. But the high frequency K6-3 CPU versions really weren't available in stores, so what I ended up with then was just barely enough.

the3dfxdude wrote on 2021-12-08, 13:56:

I did play RCTW on my slower K6-3 with GF2 when it came out. It was 30 FPS, with dips. But the high frequency K6-3 CPU versions really weren't available in stores, so what I ended up with then was just barely enough.

Nice! On my K6-2 it was mostly a slideshow. When I switched to the Thunderbird 1.33 GHz, RtCW was the first game that I played (in fact, that game was probably the main reason why I upgraded in the first place). 😀
Now, of course, being a hoarder, I now also own a few K6-3 (non-plus) CPUs and during my testing I've discovered that the K6-3, even though it's clocked lower, is much more powerful than a regular K6-2. In some titles the performance difference is insane (you basically get twice the performance with a K6-3). Not only that, but the whole experience in Windows 98 is also much better - even for basic tasks like installing games, copying files, there is a very noticeable difference (the K6-3 actually comes pretty close to a Pentium 2 in this regard).

kixs wrote on 2021-12-08, 12:07:

Nice 😀 What voltage does the cpu need at 633?

I keep it at 2.2V with a beefy cooler, and it's 100% stable.
At 2.1V it's 99% stable at this frequency, but in some titles there are occasional crashes, particularly in games that use the 3DNow! extensions.
I should mention, though, that this is a "special" chip. In fact, it's the only K6-3+ that I have which is stable at more than 600 MHz (with an out-of-spec FSB). Most of the others are stable only up to 575 MHz (115 x 5), even @ 2.3V (I did not try a higher voltage than that, because even @ 2.3V the CPU gets really hot).
K6-2+ CPUs are much better in this regard: they usually are much better overclockers, at least in my experience.

kixs wrote on 2021-12-08, 12:07:

I haven't played much with SS7 and K6+ CPUs... I've tested FSB speeds a few years ago and if I remember correctly, at least that particular board, wasn't stable above 110Mhz - could be an early revision or some other brand. So everything I test now, it's around 100Mhz FSB - but for testing CPUs it's good enough 😉 Don't know when or if ever I will put together a complete K6+ system for actually playing games on 🤣

I'm somewhat addicted to SS7 and it's still unclear to me why. 😁

ChrisK wrote on 2021-12-08, 13:17:

Recently bought two K6-III+/400ATZ for ~45 EURO each. They run well at stock voltage with 500 MHz which is my current board's max speed and at a very low wattage since they are embedded low power parts with 1.6V.
Who needs a K6-III+/550ACR 🙄

Yes if you're dealing with a board that maxes out at 83Mhz then there's not a lot of point in buying faster than a 400 or 450. Mostly your stability hassles at 83Mhz will be the board or PCI periphs, not the K6-x. (Though sub 400 chips only overclock very slightly in the non plus variants, they're very tightly binned down there)

bloodem wrote on 2021-12-08, 11:49:

Yeah, but on a board like the Asus P5A, it would be a real shame to stick with FSB100, since the speed boost when going above 10 […]
Show full quote

kixs wrote on 2021-12-08, 11:04:

These cpus aren't multiplier locked. Usually you run them at 100 base clock (95 or 105 is quite ok too) with multi up to 6X.

Yeah, but on a board like the Asus P5A, it would be a real shame to stick with FSB100, since the speed boost when going above 100MHz can be quite substantial.
My fastest SS7 build with an Asus P5A rev 1.04 (a board which I actually bought from you - thank you for that, btw 😁) is running an AMD K6-3+ 400 @ 633 MHz (FSB115 x 5.5 multi) + a GeForce 2 GTS.
This thing is both FAST (for a SS7) and extremely stable! I can play games on it that I never even dreamt of playing 20 years ago on my K6-2 500. Even Return to Castle Wolfenstein is decently playable on it, usually running @ 40+ FPS (with some dips to 10 - 15 FPS in busy scenes) - this would've been a VERY playable performance for me back in the day. 😀

What scores are you getting with that OC and GF2 GTS on 3DMark2000 and Quake 3?

rcarkk wrote on 2021-12-08, 15:13:

What scores are you getting with that OC and GF2 GTS on 3DMark2000 and Quake 3?

4473 points in 3DMark2000 (without any fine-tuning).
As for Quake 3, it seems that for some reason I didn't write down the score, but I do remember that it was very playable (with sound) even by modern standards (so 50 - 60 FPS).

Truthfully, a VIA C3 Ezra-T or Nehemiah destroys a SS7 build in every way, shape, or form (not to mention that it would even be cheaper), but nostalgia always brings me back to SS7. 😁

bloodem wrote on 2021-12-08, 16:09:

4473 points in 3DMark2000 (without any fine-tuning). As for Quake 3, it seems that for some reason I didn't write down the score […]
Show full quote

rcarkk wrote on 2021-12-08, 15:13:

What scores are you getting with that OC and GF2 GTS on 3DMark2000 and Quake 3?

4473 points in 3DMark2000 (without any fine-tuning).
As for Quake 3, it seems that for some reason I didn't write down the score, but I do remember that it was very playable (with sound) even by modern standards (so 50 - 60 FPS).

Truthfully, a VIA C3 Ezra-T or Nehemiah destroys a SS7 build in every way, shape, or form (not to mention that it would even be cheaper), but nostalgia always brings me back to SS7. 😁

Considering the GF256 DDR 32MB scores 5968 in a Tualatin-S 1.26GHz, i´m rather impressed with the extracted performance with that CPU.

https://youtu.be/tdkc7IHZ-ug?t=546

And it´s almost as fast as the Ti 200 in that video. I guess the CPU bootleneck is kicking strongly in the Ti 200

Did anyone tested the CPU test score of 3DMark with the 3DNow! optimized K6-3+ 550Mhz vs the specific Athlon optimized setting at the same clock? Or the Athlon optimization make already use of the 3DNow! instructions?

There is no way to enable 256k on a 2+ is there?

(!!!Edit from the FuTuRe!!!) yes in fact you can. Spoiler. Link further into thread.. on next page.

Sphere478 wrote on 2021-12-09, 03:19:

There is no way to enable 256k on a 2+ is there?

Uhm, you can’t add transistors that are missing from the die, so… no. 😁

bloodem wrote on 2021-12-09, 04:42:

Sphere478 wrote on 2021-12-09, 03:19:

There is no way to enable 256k on a 2+ is there?

Uhm, you can’t add transistors that are missing from the die, so… no. 😁

The k6 2+ and 3+ use the same die.

Pretty sure they edited the die pic on this, or flipped it upside down, dono. Anyway there are several pads and resistors and I think this is a non plus,

But anyway, I suspect that if someone were able to track down pics of a de lidded 2+ and 3+ we might see a difference in those resistors?

Wouldn’t it be neat if we could buy and mod 570s?!

Sphere478 wrote on 2021-12-09, 06:30:

The k6 2+ and 3+ use the same die.

Not according to Anandtech.
And even if we assume that they were originally from the same die, I would imagine that the K6-2+ are partially defective dies that had half of the L2 cache permanently disabled.

Indeed, that die shot of yours seems to be of an original AMD K6-III (non plus - 400AHX).

bloodem wrote on 2021-12-09, 07:33:

Not according to Anandtech. And even if we assume that they were originally from the same die, I would imagine that the K6-2+ ar […]
Show full quote

Sphere478 wrote on 2021-12-09, 06:30:

The k6 2+ and 3+ use the same die.

Not according to Anandtech.
And even if we assume that they were originally from the same die, I would imagine that the K6-2+ are partially defective dies that had half of the L2 cache permanently disabled.

Indeed, that die shot of yours seems to be of an original AMD K6-III (non plus - 400AHX).

They didn’t explicitly say that the 2+ and 3+ weren’t just two versions of the same die from when I read, they also missed the k6 2+570 in their talking points.

Unless I msread it. In any case, I think it’s more definitive to see some de lidded chips and compare the die size. If the resistors are in the same place, and the dies are different sizes then that puts that to bed

For sure, may just be unlocking bad cache if we are successful. That was always a risk.

It'd be interesting to know more about it. A K6-3+ 570 would be great. 😉

386SX wrote on 2021-12-09, 09:13:

It'd be interesting to know more about it. A K6-3+ 570 would be great. 😉

This got me thinking,

Might even be able to make a new heat spreader for it using old ink heat spreaders and a laser etcher. to see 570 k6-III+ On it would be pretty cool.

AMD should have built an official last epic version of the K6-3+ at 600Mhz. I know many version can get there but an official one from a very late production line should have been possible, I suppose the Duron and Athlon would have not suffered like the Am386DX-40 cpu logic that still might be considered "epic" nowdays for what it meant even if I didn't know about it in those years, only Intel brand seems existed in the common friends discussions.

386SX wrote on 2021-12-09, 12:14:

AMD should have built an official last epic version of the K6-3+ at 600Mhz. I know many version can get there but an official one from a very late production line should have been possible, I suppose the Duron and Athlon would have not suffered like the Am386DX-40 cpu logic that still might be considered "epic" nowdays for what it meant even if I didn't know about it in those years, only Intel brand seems existed in the common friends discussions.

By this time Socket 7 was budget at best, but mostly just obsolete.
There wouldn't be much of a market for a K6-III+ 600MHz, they'd rather underclock them and sell them for less.
I'm glad AMD did actually make one more die shrink after K6-III at all tbh and made TONS of these! And thankfully getting 600MHz on a + chip is reasonably common.