j^aws wrote:

If the board has a low enough voltage regulator and compatible BIOS, then it will work. And you also don't need SS7 for all those CPUs, too. Failing that, a simple S7 interposer can take care of the voltage.

Indeed. The M571 v7 has a factory setting for 2.2V and bus speeds up to 83.3MHz. With latest BIOS there are many reports of people successfully running K6-2 up to 500MHz (83.3 x 6). Apparently with mods the board can do 2.1 and even 1.8V.

brostenen wrote:

S7 can not do K6-II. For that you need SS7.
SS7 on the other hand, can do K6-II, K6-III, P166MMX and a lot of other CPU's.

My apologies for contradicting you, but this is incorrect. S7 can do K6-2. I have an ASUS TX-97 based rig that proves it.

RJDog wrote:

For those that asked, it is PC Chips M571 v7.

The key thing for K6-2/III compatibility, as I noted, is vcore capability. If your board can do 2.0-2.2V vcore, it can generally handle the full range of K6-2 and K6-III processors. Even lack of BIOS support is not a fatal deficiency. I ran my TX-97 board without a compatible BIOS for quite some time, and the .18u parts have been used successfully[1] without compatible BIOS.

As luck would have it, the M571 v7 has a BIOS patch available[2]. I probably would just stick with PMMX, though, as you have them on hand.
[1] http://web.inter.nl.net/hcc/J.Steunebrink/S1590-K6-III+.htm
[2] http://web.inter.nl.net/hcc/J.Steunebrink/k6plus.htm

S7 is older than boards that do 2.0-2.2 volts; they go as old as 3.3 volts, and some of these boards fail to post K6-2s with the latest BIOS and S7 interposers ...

gdjacobs wrote:

As luck would have it, the M571 v7 has a BIOS patch available

Awesome, thanks for the link!

gdjacobs wrote:

My apologies for contradicting you, but this is incorrect. S7 can do K6-2. I have an ASUS TX-97 based rig that proves it.

Hmmm... I never had a Socket7 system that could run K6-II.
I had a QDI board once with a 430-something chipset that could not run K6/K6-II.
And I had a Shuttle Hot 555a Rev 3.2 that could only run K6 as the fastest.
None of these however, could run a K6-II. So...

How many S7 boards can run a K6-II, even though they can only run at maximum 66mhz fsb?

Yep. I have a few 300mhz chips that are 66mhz fsb. I dont use them, but they exist.

luckybob wrote:

Yep. I have a few 300mhz chips that are 66mhz fsb. I dont use them, but they exist.

EDIT...
Sorry... Did not read the word "chip"...

Are these K6-II 66mhz FSB versions hard to come by then? As I have allways asumed that they ran at 100mhz FSB.
I am really qurious now.

My regular, non-super, socket 7 board runs an AMD K6-III like a champ at 500 MHz.

Is there a list of these boards?

j^aws wrote:

S7 is older than boards that do 2.0-2.2 volts; they go as old as 3.3 volts, and some of these boards fail to post K6-2s with the latest BIOS and S7 interposers ...

I'm certainly not surprised considering the number of players in the S7 market that some boards don't work well with K6-2 cpus despite pulling out all the stops. Some socket 7 boards are unable to deliver 2.0V due to older VRM design whereas many are able to deliver 2.0V without issue. Some have wonky BIOS builds. Some boards really only work with an Intel chip. There are socket 7 boards which don't behave well no matter what CPU is installed. Obviously the best situation for using a K6-2+ is a reliable SS7 motherboard, but the next best option is an S7 board with an appropriately patched BIOS and 2.0V vcore capability.

I think the key is to prepare yourself with as much information before starting to do a system build so that you have some idea of what is likely to work and what has a significant chance of failure. That's why the Unofficial K6+ page exists, and it's also why this forum exists. Saying that S7 is completely incompatible with K6-2 let alone K6-2/III+ is simply contradicted by the facts.

brostenen wrote:

How many S7 boards can run a K6-II, even though they can only run at maximum 66mhz fsb?

Lots... CPU bus speed has nothing to do with it. It's all about whether the VRM can provide a serviceable Vcore and whether the BIOS is patched (or just not overly picky).

Just as a note, here's Tom's Hardware kicking it old school with a T2P4 back in 2000.
http://www.tomshardware.com/reviews/oldie-tuning,216.html

feipoa wrote:

My regular, non-super, socket 7 board runs an AMD K6-III like a champ at 500 MHz.

I never liked using 83mhz FSB. I didn't want to punish my precious PCI cards.

gdjacobs wrote:

feipoa wrote:

My regular, non-super, socket 7 board runs an AMD K6-III like a champ at 500 MHz.

I never liked using 83mhz FSB. I didn't want to punish my precious PCI cards.

Normally, I don't like to run at 83 MHz either, but I have done extensive testing on this board at 83 MHz and it is appears solid. I think the graphics card I put in there was 66 MHz capable. The board's VRM has a heatsink on it, but it was getting very hot, so I added a fan.