Cosmic wrote on 2022-04-27, 17:20:

What do you all think about the TriLevel cache feature of the K6-3? Does it make a noticeable difference? I have a K6-3 450 (256K L2) and my board has 1MB cache, but I can't enable it with the K6-3 or a K6-2 500 (no L2), not even at FSB 66. Just wondering how much I might be missing out on if the cache worked...

It depends on the system. If you look at the thread for benchmarking Super 7 systems with 3D Mark 2000, the highest scores are with systems that have at least 1024k cache on the motherboard.

Conventional wisdom is that with older Socket 7 boards the motherboard's cache is still helpful so long as you don't exceed the cacheable area, which can be pretty low, such as the 64 megabytes of the TX chipset. My TXP4 with a K6-3+ @ 500 has noticeably lower memory bandwidth when measured with Sandra with the board's cache enabled. I'd always assumed this was because I had 256 megabytes of memory installed, and the cacheable area is only 64 megabytes; but yesterday I swapped the 256 meg stick of RAM for a 64 meg one, and the memory bandwidth was still noticeably lower with the board's cache enabled!

Cosmic wrote on 2022-04-27, 17:20:

What do you all think about the TriLevel cache feature of the K6-3? Does it make a noticeable difference? I have a K6-3 450 (256K L2) and my board has 1MB cache, but I can't enable it with the K6-3 or a K6-2 500 (no L2), not even at FSB 66. Just wondering how much I might be missing out on if the cache worked...

It depends on the motherboard, ram, and fsb frequency it seems.

I’ve seen having mobo L3 ebabled actually help a lot, to actually being slower. Seems like it usually helps on ss7 while s7 it can go one way or the other

Found one in the wild.

https://www.ebay.com/itm/394095618233

Sphere478 wrote on 2022-06-05, 15:26:

Found one in the wild.

https://www.ebay.com/itm/394095618233

Jesus, this price is dummy thicc.

kitten.may.cry wrote on 2022-06-05, 15:38:

Sphere478 wrote on 2022-06-05, 15:26:

Found one in the wild.

https://www.ebay.com/itm/394095618233

Jesus, this price is dummy thicc.

Actually, I think they may have lowered the price because of the whole 3+mod thing and 570s

Anyway, that price is actually not bad. I’ve seen them go for more

If you need one of these for your collection I’d get it. They don’t show up for sale often. A few of us have one including me but none of us are selling 🤣. Haha

Sphere478 wrote on 2022-06-05, 15:46:

Actually, I think they may have lowered the price because of the whole 3+mod thing and 570s […]
Show full quote

kitten.may.cry wrote on 2022-06-05, 15:38:

Sphere478 wrote on 2022-06-05, 15:26:

Found one in the wild.

https://www.ebay.com/itm/394095618233

Jesus, this price is dummy thicc.

Actually, I think they may have lowered the price because of the whole 3+mod thing and 570s

Anyway, that price is actually not bad. I’ve seen them go for more

If you need one of these for your collection I’d get it. They don’t show up for sale often. A few of us have one including me but none of us are selling 🤣. Haha

Sorry, but that is a bit mental. 0/10, wouldn't give money to snake oil salesmen.

kitten.may.cry wrote on 2022-06-05, 15:51:

Sphere478 wrote on 2022-06-05, 15:46:

Actually, I think they may have lowered the price because of the whole 3+mod thing and 570s […]
Show full quote

kitten.may.cry wrote on 2022-06-05, 15:38:

Jesus, this price is dummy thicc.

Actually, I think they may have lowered the price because of the whole 3+mod thing and 570s

Anyway, that price is actually not bad. I’ve seen them go for more

If you need one of these for your collection I’d get it. They don’t show up for sale often. A few of us have one including me but none of us are selling 🤣. Haha

Sorry, but that is a bit mental. 0/10, wouldn't give money to snake oil salesmen.

Mod a 2+ 570 then 😀

Sphere478 wrote on 2022-06-05, 16:07:

kitten.may.cry wrote on 2022-06-05, 15:51:

Sphere478 wrote on 2022-06-05, 15:46:

Actually, I think they may have lowered the price because of the whole 3+mod thing and 570s

Anyway, that price is actually not bad. I’ve seen them go for more

If you need one of these for your collection I’d get it. They don’t show up for sale often. A few of us have one including me but none of us are selling 🤣. Haha

Sorry, but that is a bit mental. 0/10, wouldn't give money to snake oil salesmen.

Mod a 2+ 570 then 😀

Do I have K6-2+ 570? No, never had one.

There is a lot of fake hype around these so called "rarest, fastest, insert adjective here" CPUs.

If you have fun modding them, so be it.

But that really doesn't translate into "Wow, this price seems a bit high, proceeds to buy it anyway"

My question is: does it help to push sales?

Stock has to be liquidated, one way or another.

Lost me, anyway I was talking about how 570s were not too expensive and you can turn them into a equal or better chip than the 550 3+. I wasn’t saying you had one. Just that it is a alternate purchase path.

IIRC my last LuckyTech P5MVP3 kit I bought from a classified had come to me with a K6-II+ 500ACZ, yet 98SE goes straight ahead and calls it a K6-III for whatever reason.

PcBytes wrote on 2022-06-05, 21:01:

IIRC my last LuckyTech P5MVP3 kit I bought from a classified had come to me with a K6-II+ 500ACZ, yet 98SE goes straight ahead and calls it a K6-III for whatever reason.

Seems 98SE sees the L2 cache and automatically assumes it must be the K6-III because that's the only K6-X CPU with L2 cache 98SE knows about.

Repo Man11 wrote on 2022-04-27, 17:43:

Cosmic wrote on 2022-04-27, 17:20:

What do you all think about the TriLevel cache feature of the K6-3? Does it make a noticeable difference? I have a K6-3 450 (256K L2) and my board has 1MB cache, but I can't enable it with the K6-3 or a K6-2 500 (no L2), not even at FSB 66. Just wondering how much I might be missing out on if the cache worked...

It depends on the system. If you look at the thread for benchmarking Super 7 systems with 3D Mark 2000, the highest scores are with systems that have at least 1024k cache on the motherboard.

Conventional wisdom is that with older Socket 7 boards the motherboard's cache is still helpful so long as you don't exceed the cacheable area, which can be pretty low, such as the 64 megabytes of the TX chipset. My TXP4 with a K6-3+ @ 500 has noticeably lower memory bandwidth when measured with Sandra with the board's cache enabled. I'd always assumed this was because I had 256 megabytes of memory installed, and the cacheable area is only 64 megabytes; but yesterday I swapped the 256 meg stick of RAM for a 64 meg one, and the memory bandwidth was still noticeably lower with the board's cache enabled!

Confirmed on my system with an ASUS TX97-XE, AMD K6-III+ @ 450 MHz, and 256 MB of RAM! 😮

I did not expect it, but I did in fact squeeze even more performance from this system by disabling the motherboard L2. I would have guessed that retrieving stuff from there would still be faster than going to the memory, but nope. Not with these K6-II / K6-III CPUs apparently...

edit: For those interested, disabling L2 on the motherboard led to a measurable increase in 3DMark2000-score: 1580 @ 1024x768 or 1603 @ 800x600. My previous highest score was 1556 points, so not a huge difference - but still in the opposite direction of what I would have expected.

leonardo wrote on 2022-06-05, 22:21:

I did not expect it, but I did in fact squeeze even more performance from this system by disabling the motherboard L2. I would have guessed that retrieving stuff from there would still be faster than going to the memory, but nope. Not with these K6-II / K6-III CPUs apparently...

edit: For those interested, disabling L2 on the motherboard led to a measurable increase in 3DMark2000-score: 1580 @ 1024x768 or 1603 @ 800x600. My previous highest score was 1556 points, so not a huge difference - but still in the opposite direction of what I would have expected.

I'm not familiar with the intimate details of the K6-2[+] or K6-III[+] but at a theoretical level this makes sense. When you add a cache to the memory hierarchy, a cache miss is actually more expensive than no cache at all. Because first you pay the penalty of waiting for the hardware to detect whether the address is in the cache or not, *plus* the time of writing back the prior data in cache line to memory if it's dirty, then retrieving the wanted data from RAM. But of course the opposite is true in that a cache hit is faster than RAM. The hope is that the hit rate is high enough that the average result is faster than going directly to RAM. Adding the on-chip L2 cache possibly messes with those probabilities such that the external cache no longer pays off. Another factor is associativity. Looks like the K6-III+ L2 cache is 256K and four-way associative. The on-motherboard 512K cache might be direct mapped (one-way associative) and if so, is effectively smaller than appears--perhaps more like having a 32K L1 cache, a 256K L2 cache, and a redundant 256K L3 cache.

Sphere478 wrote on 2022-06-05, 15:26:

Found one in the wild.

https://www.ebay.com/itm/394095618233

Laser engraving in the upper-right corner should read "550" but looks like a mess, at least on the ebay photo. I wouldn't be surprised if more and more high speed "K6-3+" pop up for sale as the news of the 2+ mod spread around the globe 😉

leonardo wrote on 2022-06-05, 22:21:

Confirmed on my system with an ASUS TX97-XE, AMD K6-III+ @ 450 MHz, and 256 MB of RAM! :-o […]
Show full quote

Repo Man11 wrote on 2022-04-27, 17:43:

Cosmic wrote on 2022-04-27, 17:20:

What do you all think about the TriLevel cache feature of the K6-3? Does it make a noticeable difference? I have a K6-3 450 (256K L2) and my board has 1MB cache, but I can't enable it with the K6-3 or a K6-2 500 (no L2), not even at FSB 66. Just wondering how much I might be missing out on if the cache worked...

It depends on the system. If you look at the thread for benchmarking Super 7 systems with 3D Mark 2000, the highest scores are with systems that have at least 1024k cache on the motherboard.

Conventional wisdom is that with older Socket 7 boards the motherboard's cache is still helpful so long as you don't exceed the cacheable area, which can be pretty low, such as the 64 megabytes of the TX chipset. My TXP4 with a K6-3+ @ 500 has noticeably lower memory bandwidth when measured with Sandra with the board's cache enabled. I'd always assumed this was because I had 256 megabytes of memory installed, and the cacheable area is only 64 megabytes; but yesterday I swapped the 256 meg stick of RAM for a 64 meg one, and the memory bandwidth was still noticeably lower with the board's cache enabled!

Confirmed on my system with an ASUS TX97-XE, AMD K6-III+ @ 450 MHz, and 256 MB of RAM! 😮

I did not expect it, but I did in fact squeeze even more performance from this system by disabling the motherboard L2. I would have guessed that retrieving stuff from there would still be faster than going to the memory, but nope. Not with these K6-II / K6-III CPUs apparently...

edit: For those interested, disabling L2 on the motherboard led to a measurable increase in 3DMark2000-score: 1580 @ 1024x768 or 1603 @ 800x600. My previous highest score was 1556 points, so not a huge difference - but still in the opposite direction of what I would have expected.

Yep, some are better with three level, some are worse. You’ll just have to test. But usually ss7 is better with, while s5/7 can be either way.

RaiderOfLostVoodoo wrote on 2022-04-27, 15:47:

Sphere478 wrote on 2022-04-27, 10:07:

At this point, these are purely a collectors item given the 570 2+ chips that are cheap, plentiful an unlockable.

SUCCESSFUL K6-2+ to K6-3+ Full Cache Enable Mod

Even before the mod was discovered, the 550ACR was a collectors item only.
My 400ATZ (low voltage) can be overclocked to 550MHz if I increase the voltage from 1.6V to 1.7V.

Basically this. A lot of the times overclocking can get you to the effective limit of the last processor stepping of the architecture.
With locked multipliers its more pronounced because additional FSB gains additional speed.

Like with PII based Mendocino Celerons, the best one you can get is.. a 366MHz model. Almost all of them overclock to 100MHz FSB, and at 5.5x100=550MHz thats pretty much the fastest a Celeron 1 can get. While 6x100 400->600MHz and 5.5x112 may be possible, 600 is pretty much the ceiling of that lot, and much less obtainable.
You can get a 8x66=533MHz Celeron out of the box but whats the point?

So people cant get a 1400MHz P3-S Tualatin for their retro needs? Whell then let them eat 1100MHz TuaCeleron, and just overclock it to 11x133=1466MHz enjoying the very highest end of Talatin performance. Its less trivial than with the 366 parts because not all of them have 33% tuning potential, but still doable.

Highest end Socket A is the same, Barton cores cap out at around 2300MHz something with air cooling, so a rare-ish 11x200=2200MHz Athlon XP 3200+ doesnt really have much tuning potential. That cant be said about the 11x166=1833MHz 2500+ models tho, which can mostly be overclocked to 200MHz FSB without a problem making them 3200+ processors with a few mouse clicks. 11.5x166 2600+ is bit more problematic because thats hitting the limit, but its possible with a good model in a good board. Some people said that the actual limit is around 2400-2500MHz-ish, but im fairly sure thats late stepping XP-M + unlocked multiplier + great motherboard + 500+MHz (A-DATA Vitesta) memory + overblown cooling type crazyness.
The common plebs at the time had 2500->3200+ mods everywhere, even with shitty parts, and they were thankful for it.

With Socket 7 systems your practically not even overclocking. Since even late motherboards need jumpers or DIP switches to set the multiplier, FSB, and core voltage, the board doesnt even know what the rated speed was in the first place. So paying top dollars for an 550MHz part instead of getting a mobile version far cheaper is just pure dick swinging and feeding the OCD monster.

I wish this could be done so easily to Slot A Athlon parts, but those are pretty crappy overclockers, with or without a goldfinger device.

cskamacska wrote on 2022-06-06, 08:26:

I wish this could be done so easily to Slot A Athlon parts, but those are pretty crappy overclockers, with or without a goldfinger device.

Agree with most of what you said but... huh?!
Quite a few Plutos are actually faster chips in disguise. This was common knowledge even 22 years ago (and one of the reasons if not THE reason why Goldfinger devices existed in the first place).
I for one have about 10 Athlons, and four of those have faster dies than what is written on the plastic enclosure. Two of them (both 700 MHz parts) have 900 MHz dies and they both overclock just fine @ 1 GHz / 1.75V.

Granted, you still need to have a bit of luck to get your hands on such a CPU, but these are far from being rare.

cskamacska wrote on 2022-06-06, 08:26:

Like with PII based Mendocino Celerons, the best one you can get is.. a 366MHz model. Almost all of them overclock to 100MHz FSB, and at 5.5x100=550MHz thats pretty much the fastest a Celeron 1 can get. While 6x100 400->600MHz and 5.5x112 may be possible, 600 is pretty much the ceiling of that lot, and much less obtainable.
You can get a 8x66=533MHz Celeron out of the box but whats the point?

440LX, especially the first generation of s370 440LX boards since these won't work with slot CPUs and the chipset probably won't overclock much either.

cskamacska wrote on 2022-06-06, 08:26:

With Socket 7 systems your practically not even overclocking. Since even late motherboards need jumpers or DIP switches to set the multiplier, FSB, and core voltage, the board doesnt even know what the rated speed was in the first place. So paying top dollars for an 550MHz part instead of getting a mobile version far cheaper is just pure dick swinging and feeding the OCD monster.

The 570s have been showing very good yeilds and are usually cheaper than the low voltage variants. There have been even a few cases of north of 650mhz on air with some of them. They are imho the most common sense socket 7 performance purchase at the moment. The mod is required though. But It’s not too hard if you follow the guide.

Some people are even upgrading them to liquid metal with a athalon IHS

Sphere478 wrote on 2022-06-06, 09:14:

cskamacska wrote on 2022-06-06, 08:26:

With Socket 7 systems your practically not even overclocking. Since even late motherboards need jumpers or DIP switches to set the multiplier, FSB, and core voltage, the board doesnt even know what the rated speed was in the first place. So paying top dollars for an 550MHz part instead of getting a mobile version far cheaper is just pure dick swinging and feeding the OCD monster.

The 570s have been showing very good yeilds and are usually cheaper than the low voltage variants. There have been even a few cases of north of 650mhz on air with some of them. They are imho the most common sense socket 7 performance purchase at the moment. The mod is required though. But It’s not too hard if you follow the guide.

Some people are even upgrading them to liquid metal with a athalon IHS

I think you meant Athlon? Athlons don't have IHSs though, they come with a naked die. Or you meant A64?