I was wondering if you ever tried using an AMD K6-2+ CPU in either of these boards, and if you did - did it work?

I tried a K6-2+/570 yesterday, jumpered for 66x2(x6), should be 400MHz underclock. It POSTs and I can enter the BIOS, but it will not boot. After the IDE autodetection sequence on the POST screen it always goes into a reboot loop. I tried higher voltages (up to 2.2V from the default 2.0), no change. I also tried lower multipliers like 3.5 and 3, still no change, still goes into this reboot loop - doesn't ever go anywhere near booting DOS from either floppy or CF.
(if you recall, I did flash the latest modded bios with support for newer AMD CPUs, it is recognized on the POST screen as a "AMD K6-2 at 366MHz" which is odd)

stamasd wrote on 2022-02-08, 13:22:

I was wondering if you ever tried using an AMD K6-2+ CPU in either of these boards, and if you did - did it work?

I tried a K6-2+/570 yesterday, jumpered for 66x2(x6), should be 400MHz underclock. It POSTs and I can enter the BIOS, but it will not boot. After the IDE autodetection sequence on the POST screen it always goes into a reboot loop. I tried higher voltages (up to 2.2V from the default 2.0), no change. I also tried lower multipliers like 3.5 and 3, still no change, still goes into this reboot loop - doesn't ever go anywhere near booting DOS from either floppy or CF.
(if you recall, I did flash the latest modded bios with support for newer AMD CPUs, it is recognized on the POST screen as a "AMD K6-2 at 366MHz" which is odd)

If you install a smp os kernel and attempt to boot with one processor it will bsod. Or at least that’s my experience with windows xp.

I assume this isn’t the case for you though as you have only one socket still

I haven’t done much playing around with k6-2/3+ on these boards. But they should work. You should be able to get 66x6x working at 400mhz though due to some weird glitch it sometimes actually boots at 366mhz or 400 but detects at 366. I’ve noticed both actually being at 366 and falsely detecting 366 as well as 400 and actually being 400 I don’t know what that’s about but it fluctuates between reboots.

Honestly, as I’ve stated before a k6-3+ at 400 should be the fastest this board is capable of. Even faster in most tasks than a dual processor. In one of my other threads I talk about this. I think it’s my dual pentium build thread.

If I recall… I think there was a specific setting under chipset features that may be causing your issue.

Let me give you some bios settings that I use on my 233 dual with 4x128mb 60ns

Try changing one setting at a time under chipset features. I think one of them is a problem child with k6 + but don’t recall which

My board isn't modded for dual socket yet, still just one. And I'm just trying to get DOS booted, which it doesn't want to with the K6-2+

(edit) yeah about the same settings as mine IIRC (I'm not home now so cannot check exactly) except for the PS/2 mouse which I have enabled because I've got a socket for it now. 😀

stamasd wrote on 2022-02-08, 14:04:

My board isn't modded for dual socket yet, still just one. And I'm just trying to get DOS booted, which it doesn't want to with the K6-2+

(edit) yeah about the same settings as mine IIRC (I'm not home now so cannot check exactly) except for the PS/2 mouse which I have enabled because I've got a socket for it now. 😀

I understood that when I wrote the reply. I am doing a test right now to locate the setting. I experienced the problem and have overcome it, now to find out which of the several settings that it was

I believe your problem setting is system bios cached

No, I know system bios caching is set to disabled. I specifically turned that off.

stamasd wrote on 2022-02-08, 14:32:

No, I know system bios caching is set to disabled. I specifically turned that off.

I posted that soon as I got windows ME splash screen to load. But it didn’t fully boot. System bios cachable was part of my problem. Investigating additional settings

You know what, I’m remembering now that I believe the last time I ran a k6 on this board it was a k6-3 not a +

Right now I am attempting to run your chip (a 570 2+), I am continuing to have issues making it to the desktop.it might be that the os must be reinstalled for such a change.. will update if any progress

Edit: never mind it booted. I think I just wasn’t waiting long enough. (I’m booting windows ME from a microdrive on 8-bit Isa 🤣

Confirming optimal stable bios settings.Will update with new post when I have it. Last thing that I changed was usb keyboard but I don’t think that was it. In fact I think system bios cachable was the only thing that was stopping mine from working.

Okay, desktop loaded, running very slowly. I just realized I’m still set to dual cpu. Will set that jumper back on next reboot

It’s been booting at 366 btw like I was saying. I suspect something about bf2 or the way bf0,1 is pulled may be making it think 5.5 multi has been set. I can try a test later to see if my power leap solves this, if so, a hard mod may be in order for the mainboard.

Okay, final edit here basically mine is booting fine with a 570 2+ using the bios settings I posted with system bios cachable turned off.

Try a cmos defaults/ cmos clear and set the settings again

The single/dual jumper made no difference.

See updated post^

So the computer is running slower than it normally does. I’m going to try moving the xt-IDE and removing the isa soundblaster

I did make it to cpu-z though after extreemly long load times. More so than normal even for this drive.

As you can see on this boot I got 400 mhz. Sometimes cpu-z will report 366, sometimes it will report 400, sometimes bios will report 366, sometimes it will report 400.

Moving and removing cards did nothing

I next tried mini xp from cd drive. This booted at basically normal speed.

Yeah. This is all running fast from mini xp. I’m guessing I need to reinstall ME

OK thanks will try again tonight when I get home.

Well something worked. I reset the CMOS to defaults, only turned back a few things (PS/2 mouse and IDE block mode and UDMA) and it booted into DOS, stable, ran benchmarks etc. It's still shown as 366MHz on the POST screen but 399MHz in cpuchk etc..

stamasd wrote on 2022-02-09, 00:46:

Well something worked. I reset the CMOS to defaults, only turned back a few things (PS/2 mouse and IDE block mode and UDMA) and it booted into DOS, stable, ran benchmarks etc. It's still shown as 366MHz on the POST screen but 399MHz in cpuchk etc..

Yeah, at some point we should try to get to the bottom of that, what’s really weird is that I have actually seen it be at 366 in cpuz something that shouldn’t be possible without a ss7 one could dismiss it as faulty bios reporting if not for that.

Congrats on the successful test!

I’m considering doing some k6 2+ vs k6 2 vs k6 3 vs k6 3+ vs cache on vs cache off benchmarks on this board.

It will have to wait for some more free time though.

I got xp sp2 installed and am ready for any benchmarks you may be curious about, but you basically have the same setup as me now. So can probably run them yourself, never the less if anyone else or you have requests it’s ready.

Here is a super pi 1m

Well no it's not the same setup. Turns out, I only have a few 8M 72-pin FPM memory modules (and a few 8M EDO) - nothing bigger than 8M. So the most I can put on this board is 64M. 😀 Need to acquire more memory.

Honestly, I can't figure out what it doesn't like in BIOS settings.
So I had the BIOS settings working with the K6-2+. Then without touching any of those, I changed the CPU for a K6-2/400. Not even changing any of the jumpers. And of course, it went into the reboot loop.
I went back into the BIOS and loaded defaults, and it started booting correctly. Then one by one I started turning back settings in BIOS, rebooting after each one. It kept booting correctly until I had almost everything turned on/up in the BIOS.

I think it just wants a parameter reset every time you change the CPU. I don't think there's any one particular setting that sends it into the reboot loop.
Reset to defaults, then turn back everything on that you want, and it works.

(also for some reason I'm getting a much better score in Quake with the K6-2/400 compared to the K6-2+/570 at 400. Same FSB, same multiplier, latter has cache too but I'm getting 51.2FPS with the former vs. 38.8FPS with the latter)

stamasd wrote on 2022-02-11, 23:33:

Honestly, I can't figure out what it doesn't like in BIOS settings. So I had the BIOS settings working with the K6-2+. Then wit […]
Show full quote

Honestly, I can't figure out what it doesn't like in BIOS settings.
So I had the BIOS settings working with the K6-2+. Then without touching any of those, I changed the CPU for a K6-2/400. Not even changing any of the jumpers. And of course, it went into the reboot loop.
I went back into the BIOS and loaded defaults, and it started booting correctly. Then one by one I started turning back settings in BIOS, rebooting after each one. It kept booting correctly until I had almost everything turned on/up in the BIOS.

I think it just wants a parameter reset every time you change the CPU. I don't think there's any one particular setting that sends it into the reboot loop.
Reset to defaults, then turn back everything on that you want, and it works.

(also for some reason I'm getting a much better score in Quake with the K6-2/400 compared to the K6-2+/570 at 400. Same FSB, same multiplier, latter has cache too but I'm getting 51.2FPS with the former vs. 38.8FPS with the latter)

I wonder if you have to pull wt/wb high on the back of the board through a 1k resistor.

(See the p5a simple mod thread)
K6-2/3+ Success on Asus P5A 1.06 - simple mod

Also, yes I think you need to reset the bios when swapping around cpus. May be a bios bug.🤷‍♂️

You can dump CMOS contents, replace CPUs, go thru whole reset and set everything again thing, dump CMOS again and compare

Be careful with the configuration of simms on this board the only way to make sure the config is correct is to use unique data which memtest does not do.

On UltimateRetro discord catsay has made a 128mb simm design you could use to make some simms.

Or if you want these are the ones I have
https://www.ebay.com/itm/303649179445

This board is exceedingly picky with RAM. I found some extra 72pin SIMMs, and tried to get the memory up to a decent configuration and install win98. Apart from one pair of 8MB SIMMs plus one pair of 16MB ones (so a total of 48MB) the board will not even boot into DOS. I tried a number of other SIMM pairs, ranging from 8MB FPM to 32MB EDO; I played with parity and timing settings in the BIOS until I started seeing red.
Except for one very specific configuration (with that one 8+8MB pair in slots 1 and 2, and the 16+16MB pair in slots 3 and 4), the board won't even get to DOS booting. It complains of memory parity failure, and gives me the option to press F1 to disable NMI (after which it continues booting) or F2 to reboot. But I don't want to boot with NMI disabled.
Any memory nodules I put in either slots 5+6 and/or 7+8, it gives me the same error - including the ones that work in slots 1/2 and 3/4. And in the first 4 slots, the only ones that don't give me that error at boot are the ones above, and only in that specific order. If I swap the slots for the 2 pairs, I get the error again. I must have tried about 12 pairs of SIMMs, all of which are tested and working well in other motherboards.

And even with the 4 modules that don't give me the error when booting DOS - when I try to install win98se, I get that error soon after I start setup. 🙁

Yes, I did try the trick with resetting CMOS to defaults (which worked when swapping the CPU) but in this case it didn't help. Still get the error.

This instability of this Tyan dual pentium board was confirmed back in the day and customer lost money on it because seller did not come back when we visited next time. Corrupts the windows.

Cheers,

stamasd wrote on 2022-02-14, 12:23:

This board is exceedingly picky with RAM. I found some extra 72pin SIMMs, and tried to get the memory up to a decent configurati […]
Show full quote

This board is exceedingly picky with RAM. I found some extra 72pin SIMMs, and tried to get the memory up to a decent configuration and install win98. Apart from one pair of 8MB SIMMs plus one pair of 16MB ones (so a total of 48MB) the board will not even boot into DOS. I tried a number of other SIMM pairs, ranging from 8MB FPM to 32MB EDO; I played with parity and timing settings in the BIOS until I started seeing red.
Except for one very specific configuration (with that one 8+8MB pair in slots 1 and 2, and the 16+16MB pair in slots 3 and 4), the board won't even get to DOS booting. It complains of memory parity failure, and gives me the option to press F1 to disable NMI (after which it continues booting) or F2 to reboot. But I don't want to boot with NMI disabled.
Any memory nodules I put in either slots 5+6 and/or 7+8, it gives me the same error - including the ones that work in slots 1/2 and 3/4. And in the first 4 slots, the only ones that don't give me that error at boot are the ones above, and only in that specific order. If I swap the slots for the 2 pairs, I get the error again. I must have tried about 12 pairs of SIMMs, all of which are tested and working well in other motherboards.

And even with the 4 modules that don't give me the error when booting DOS - when I try to install win98se, I get that error soon after I start setup. 🙁

Yes, I did try the trick with resetting CMOS to defaults (which worked when swapping the CPU) but in this case it didn't help. Still get the error.

Just order four of those 128mb sticks I linked.

They are confirmed to work without issues in slots 1-4