Edit 2:
Problem: random reboots at loading; sometimes if it goes through it hangs.
Like if there was a timer.

Adding +0.1 to Vcore makes it more stable, tried with all cpus except p233mmx, that works just fine.

Tried K6/2-333/366 and it seemed better with +0.1
But had random reboots anyway with win2K, 98 didn't.

IBM 6x86 PR300 (3*75mhz) rebooted @ 2.9 but was booting in Win2K with +0.1, before it just rebooted at loading screen or just after finishing.

Questions:

1) Could be a faulty V regulator? I tried many PSUs and same issue.
2) if vcore drops suddenly could that make the system reboot?
3) could it be ram related? like 2k is less fault tolerant...

I still use +0.1V on vcore.

Put in a new graphics card (agp instead of pci) and now it works. Pci vid card has issues.
2nd pci video card that fails on me. Good for checking cpus in dos.

I think that win98 goes lowest res without drivers and then works ok. Win 2K goes for a resolution that isn't supported and then reboots on video mem issues.
Like those latest fake video cards.

Old stuff decides to die in the worst moments... 🙁

Edit:

Every time I change cpu I, in 98 it boots and loads correctly.
In W2K I have to go to safe mode and reboot in normal mode. Otherwise I get the reboot loop... WTF????? 😀 🤣

This board is driving me crazy, some cpus work, others don't.
K6 has something with this mobo that I can't find, I'll try the last known bios f7b and hope for the best.

If I can't find what's wrong I'll keep it as a test board for ss7 cpus.

Today was a boring day...

Nexxen wrote on 2021-07-04, 19:23:

This board is driving me crazy, some cpus work, others don't. K6 has something with this mobo that I can't find, I'll try the la […]
Show full quote

This board is driving me crazy, some cpus work, others don't.
K6 has something with this mobo that I can't find, I'll try the last known bios f7b and hope for the best.

If I can't find what's wrong I'll keep it as a test board for ss7 cpus.

Today was a boring day...

It's really weird. Have you noticed some regularity about hangings and errors?
Have you tried to change everything in the system (including IDE cables) but the motherboard?
Also I would play with settings: disable L2 (external) cache, set loose timings for RAM, set lower speed (set 66MHz instead of 100MHz for K6-2), clear cmos, load setup/bios defaults, disable all unused int. peripherals and so on.

Roman555 wrote on 2021-07-05, 08:37:

It's really weird. Have you noticed some regularity about hangings and errors? Have you tried to change everything in the syste […]
Show full quote

Nexxen wrote on 2021-07-04, 19:23:

This board is driving me crazy, some cpus work, others don't. K6 has something with this mobo that I can't find, I'll try the la […]
Show full quote

This board is driving me crazy, some cpus work, others don't.
K6 has something with this mobo that I can't find, I'll try the last known bios f7b and hope for the best.

If I can't find what's wrong I'll keep it as a test board for ss7 cpus.

Today was a boring day...

It's really weird. Have you noticed some regularity about hangings and errors?
Have you tried to change everything in the system (including IDE cables) but the motherboard?
Also I would play with settings: disable L2 (external) cache, set loose timings for RAM, set lower speed (set 66MHz instead of 100MHz for K6-2), clear cmos, load setup/bios defaults, disable all unused int. peripherals and so on.

Hi!
I did it all. Many times. Ram, hd, cd-rom, dvd-rom, cpus, disable enable everything... I'm going to desolder old vcore caps and put new ones (you never know).
The time you need a K6 pundit!
It's old stuff, you figure out the steps to have everything 100% and you are done. But this is beyond me.

I believe it has to do with FSB and fixed ratios.
I'm not a BIOS expert but W98 seems to be more tolerant, but still has issues.

Pentium 233 mmx works well with 98+2k; K6-300 works perfectly with 98+2k.

Flashing to latest bios and see if anything changes.

Oddly in W98 cpuz reports correct data, in W2K it gives half the FSB (233mhz as 116; k6 as 150).
Gonna drop a line to the cpuz guy.

I swapped the k6-300 with a 2-333.
When it loads w98 it reboots after 15 seconds after desktop appears. always
Back to k6-300 and it's all good.

🤣

Nexxen wrote on 2021-07-05, 09:41:

Hi! I did it all. Many times. Ram, hd, cd-rom, dvd-rom, cpus, disable enable everything... I'm going to desolder old vcore caps […]
Show full quote

Hi!
I did it all. Many times. Ram, hd, cd-rom, dvd-rom, cpus, disable enable everything... I'm going to desolder old vcore caps and put new ones (you never know).
The time you need a K6 pundit!
It's old stuff, you figure out the steps to have everything 100% and you are done. But this is beyond me.

I believe it has to do with FSB and fixed ratios.
I'm not a BIOS expert but W98 seems to be more tolerant, but still has issues.

Pentium 233 mmx works well with 98+2k; K6-300 works perfectly with 98+2k.

Flashing to latest bios and see if anything changes.

Oddly in W98 cpuz reports correct data, in W2K it gives half the FSB (233mhz as 116; k6 as 150).
Gonna drop a line to the cpuz guy.

Hi !
Maybe the recapping will help. Good luck!
Also I'd like to mention linear voltage regulator Q6 LX8383A that makes +3.3v for many components.
Just check if the voltage is correct (voltmeter, black pin to GND, red pin to Vout - pin2 or TAB of Q6)

Roman555 wrote on 2021-07-05, 14:04:

Hi ! Maybe the recapping will help. Good luck! Also I'd like to mention linear voltage regulator Q6 LX8383A that makes +3.3v for […]
Show full quote

Nexxen wrote on 2021-07-05, 09:41:

Hi! I did it all. Many times. Ram, hd, cd-rom, dvd-rom, cpus, disable enable everything... I'm going to desolder old vcore caps […]
Show full quote

Hi!
I did it all. Many times. Ram, hd, cd-rom, dvd-rom, cpus, disable enable everything... I'm going to desolder old vcore caps and put new ones (you never know).
The time you need a K6 pundit!
It's old stuff, you figure out the steps to have everything 100% and you are done. But this is beyond me.

I believe it has to do with FSB and fixed ratios.
I'm not a BIOS expert but W98 seems to be more tolerant, but still has issues.

Pentium 233 mmx works well with 98+2k; K6-300 works perfectly with 98+2k.

Flashing to latest bios and see if anything changes.

Oddly in W98 cpuz reports correct data, in W2K it gives half the FSB (233mhz as 116; k6 as 150).
Gonna drop a line to the cpuz guy.

Hi !
Maybe the recapping will help. Good luck!
Also I'd like to mention linear voltage regulator Q6 LX8383A that makes +3.3v for many components.
Just check if the voltage is correct (voltmeter, black pin to GND, red pin to Vout - pin2 or TAB of Q6)

I'm looking at them with Lx below, then fdb above and SW on top

LX8383A
----------
/ pin 1 from left 2.28
/ pin 2 (middle) 3.53
/ pin 3 on the right 5.16

FDb6030L

left pin 2.21
middle 5.17
right 2.76

I'll recap tonight. It should hang with P233 and K6300 but it works just well.
K6-2 or -III and it goes randome reboots with 2K...

After recapping I'll call it and leave it as it is fro W98 stuff only.

Nexxen wrote on 2021-07-05, 14:22:

I'm looking at them with Lx below, then fdb above and SW on top […]
Show full quote

I'm looking at them with Lx below, then fdb above and SW on top

LX8383A
----------
/ pin 1 from left 2.28
/ pin 2 (middle) 3.53
/ pin 3 on the right 5.16

FDb6030L

left pin 2.21
middle 5.17
right 2.76

I'll recap tonight. It should hang with P233 and K6300 but it works just well.
K6-2 or -III and it goes randome reboots with 2K...

After recapping I'll call it and leave it as it is fro W98 stuff only.

LX8383A - Vout =3.53V - it seems Ok.
FDb6030L - 2.76V - it seems Ok for 2.8v Vcore

P.S. By the way, GA-5AA rev 3.2 has got better VRM (2 MOSFETs) .

Roman555 wrote on 2021-07-05, 16:13:

LX8383A - Vout =3.53V - it seems Ok. FDb6030L - 2.76V - it seems Ok for 2.8v Vcore […]
Show full quote

Nexxen wrote on 2021-07-05, 14:22:

I'm looking at them with Lx below, then fdb above and SW on top […]
Show full quote

I'm looking at them with Lx below, then fdb above and SW on top

LX8383A
----------
/ pin 1 from left 2.28
/ pin 2 (middle) 3.53
/ pin 3 on the right 5.16

FDb6030L

left pin 2.21
middle 5.17
right 2.76

I'll recap tonight. It should hang with P233 and K6300 but it works just well.
K6-2 or -III and it goes randome reboots with 2K...

After recapping I'll call it and leave it as it is fro W98 stuff only.

LX8383A - Vout =3.53V - it seems Ok.
FDb6030L - 2.76V - it seems Ok for 2.8v Vcore

P.S. By the way, GA-5AA rev 3.2 has got better VRM (2 MOSFETs) .

But costs both kedneys... 😀

it's 2.21 that goes to cpu (k6-300 is @ 2.2V), other leg has 2.76

Nexxen wrote on 2021-07-05, 17:49:

But costs both kedneys... 😀

it's 2.21 that goes to cpu (k6-300 is @ 2.2V), other leg has 2.76

Ah, yes. I didn't pay attention that the MOSFET was above LDO so the left/right were inverted 😀

Recapped 5x 10V 1000µF above the cpu socket.
None were bulging but 3 were pregnant! 😀

No more random reboots with k6-2/iii, MII, 6x86.

There must be some specific technical stuff to explain why with P233 and K-6/300 it didn't reboot.

Still need to solve why cpuz reports half the fsb in w2K. Will run benchmarks to see if it really does work @ right fsb (100mhz).
Could be a bios setting I'm doing wrong.

Edit: AIDA 32 reports correct settings.
RAM read write are in range with other k6-2/iii shown in benchmarks @100mhz ram.

Nexxen wrote on 2021-07-06, 18:35:

Recapped 5x 10V 1000µF above the cpu socket. None were bulging but 3 were pregnant! :) […]
Show full quote

Recapped 5x 10V 1000µF above the cpu socket.
None were bulging but 3 were pregnant! 😀

No more random reboots with k6-2/iii, MII, 6x86.

There must be some specific technical stuff to explain why with P233 and K-6/300 it didn't reboot.

Glad to read this 😀
I guess it's because P233 and K6-300 draw less power from the Core VRM than K6-2/3 and the others.

Benchmarks with PCmark 2002:

- w98se: cpu 502
mem 512

- w2k: cpu 275
mem 259

W2K @ 50 mhz FSB
W98 @ 100 mhz FSB

Why W2k works at 1/2 FSB I can't figure out.

Reading this made me happy! Never give up! I have a rev 3.2 that is not working but it has bulged caps, I have hope that changing caps will repair it.
But for now I need to fix my new P5A for my depressions sake 🙁

I know there is a bug for the half FSB you will find info on google 😀

Skalabala wrote on 2021-07-07, 16:49:

Reading this made me happy! Never give up! I have a rev 3.2 that is not working but it has bulged caps, I have hope that changing caps will repair it.
But for now I need to fix my new P5A for my depressions sake 🙁

I know there is a bug for the half FSB you will find info on google 😀

Thank you for dropping a line.
I was already scheduling a shrink session 😀 This new info clears up a lot and gives me a starting point, thanks man!

It's a massive bug:
PCMark 2002
- 2K cpu 334 memory 412
- 98 cpu 672 memory 755

This is gigantic. W2K serves no purpose at this point.
I'll look for the half bus bug.

Caps on my board were bulging but on the bottom. I saw another one with that "belly bulge" and I have to order more caps.
I have to thank Roman for his help as well.
VRM caps are close to the socket, I'll try those first (and ones that are clearly dead). If I had done it immediately I would have wasted less time.

Maybe there's a way to set the FSB like the multiplier.
I have a new quest with many side quests!! Plenty of Xps 😀

After a quick look it is indeed a BIOS issue with W2K not taking installing ACPI functionality.

1) someone posted that installing with the latest BIOS (F7b - beta) will solve the issue.
I'll try and report.

2) suggestion to install with APM disabled and then reinstall 2k with APM enabled in bios

3) install and then "repair" installation

Fingers crossed

I installed 2K with F6 bios and then installed SP5.1 and updates rollup 2.

Windows XP Sp2 installs just fine and reports the correct FSB speed.
Previous results were:
K6-2/400
- w98se: cpu 502
mem 512

- w2k: cpu 275
mem 259
and

K6-2/450
- 2K cpu 334 memory 412
- 98 cpu 672 memory 755

PCMark 2002 results K6-iii/400:
Win XP SP2
Cpu score: 638
Memory score: 573

I couldn't make W2K work at full FSB speed (fresh install with bios F6/F7b; repair option), but XP sp1 might be just enough to cover all issues, SP2 is good but sometimes slow with 768 MB of ram but normally pretty snappy (no antivirus or firewall). SP3 is too heavy for better systems and I'm not even gonna try for the sake of it.

I have another SS7 with VIA chipset, I'll test that next.

Nexxen wrote on 2021-07-08, 10:21:

I couldn't make W2K work at full FSB speed (fresh install with bios F6/F7b; repair option), but XP sp1 might be just enough to cover all issues

It's amazing! I've never thought W2K can be problematic on some period-correct hardware.

Roman555 wrote on 2021-07-08, 14:58:

Nexxen wrote on 2021-07-08, 10:21:

I couldn't make W2K work at full FSB speed (fresh install with bios F6/F7b; repair option), but XP sp1 might be just enough to cover all issues

It's amazing! I've never thought W2K can be problematic on some period-correct hardware.

I think it's more on the NB vs bad drivers and bugs. It was a small market cut and they didn't bother.
IMO
--------------------

Ran PCMArk 2002 twice on a SOYO SY-5EMA+:

XP SP2:
1st run
cpu 607
mem 771

2nd run
cpu 615
mem 773

VIA MVP3 chipset is faster than ALI's for memory speed, but it's 1mb vs 512kb.
Cpu a little slower.