Hans Tork wrote on 2025-09-28, 03:58:

Edit2: It seems even the yz version of the bios has the support for 683. Weird

Keep in mind that early steppings of cpu's in Engineering Sample format are shared with motherboard (and Bios) developers long before the end products hit the market.
The desktop Pentium 3 cpuid overview looks like this:
cpuid / step / family
672 / B0 / Katmai
673 / C0 / Katmai
681 / A2 / Coppermine
683 / B0 / Coppermine
686 / C0 / Coppermine
68A / D0 / Coppermine
6B1 / A1 / Tualatin
6B4 / B1 / Tualatin

PARKE wrote on 2025-09-28, 13:34:

The desktop Pentium 3 cpuid overview looks like this: cpuid / step / family 672 / B0 / Katmai 673 / C0 / Katmai […]
Show full quote

The desktop Pentium 3 cpuid overview looks like this:
cpuid / step / family
672 / B0 / Katmai
673 / C0 / Katmai

This is for motherboards with Slot 1.
It should contain microcodes starting with the Pentium Pro.
The VL6 is a motherboard with Socket 370.
Also, with a small BIOS chip, there's no point in cluttering it.

I don't know why there aren't 665/ B0 - Celeron Mendocino.
Perhaps the motherboard doesn't support them for some reason.

shevalier wrote on 2025-09-28, 13:44:

This is for motherboards with Slot 1. It should contain microcodes starting with the Pentium Pro. The VL6 is a motherboard with […]
Show full quote

PARKE wrote on 2025-09-28, 13:34:

The desktop Pentium 3 cpuid overview looks like this: cpuid / step / family 672 / B0 / Katmai 673 / C0 / Katmai […]
Show full quote

The desktop Pentium 3 cpuid overview looks like this:
cpuid / step / family
672 / B0 / Katmai
673 / C0 / Katmai

This is for motherboards with Slot 1.
It should contain microcodes starting with the Pentium Pro.
The VL6 is a motherboard with Socket 370.
Also, with a small BIOS chip, there's no point in cluttering it.

I don't know why there aren't 665/ B0 - Celeron Mendocino.
Perhaps the motherboard doesn't support them for some reason.

Thanks I do plan to try recapping the board. I have very little experience with soldering and only did minor soldering/recapping on a gpu.

As for the Celeron Mendocino support, the retro web site claims it does support it and I think the ebay seller also tested the board with a celeron processor.

https://theretroweb.com/motherboards/s/abit-ab-vl6#chips

CPUCODE.BIN is just a file of microcodes arranged sequentially.
https://github.com/platomav/CPUMicrocodes/tree/master/Intel

Simply download the latest versions from the repository and combine them into a single file without empty spaces.
In Hexredactor, or using file merge commands in Windows CLI.
Then, using the AWARD CBRom utility, simply replace this module.
Usually for old BIOS version 1.55 is recommended.
It's not rocket science.

But, of course, first you need to get the motherboard working properly.

PS Re: Abit VL6 CPU support
For Mendocino microcode plased in noncompressed zone of BIOS.

shevalier wrote on 2025-09-28, 15:13:

CPUCODE.BIN is just a file of microcodes arranged sequentially. https://github.com/platomav/CPUMicrocodes/tree/master/Intel […]
Show full quote

CPUCODE.BIN is just a file of microcodes arranged sequentially.
https://github.com/platomav/CPUMicrocodes/tree/master/Intel

Simply download the latest versions from the repository and combine them into a single file without empty spaces.
In Hexredactor, or using file merge commands in Windows CLI.
Then, using the AWARD CBRom utility, simply replace this module.
Usually for old BIOS version 1.55 is recommended.
It's not rocket science.

But, of course, first you need to get the motherboard working properly.

PS Re: Abit VL6 CPU support
For Mendocino microcode plased in noncompressed zone of BIOS.

Yeah I am now focussing on the recapping part. However I did look at using CBROM to insert microcodes(courtesy AI).

Also are there any good Socket 370 motherboards with decent caps and which are hassle free to get up and running. The ASUS board seemed good but had input issues while for this board I think I need the recapping.

Hans Tork wrote on 2025-09-28, 14:31:

I don't know why there aren't 665/ B0 - Celeron Mendocino.

As for the Celeron Mendocino support, the retro web site claims it does support it.

The VL6_7K BIOS has Mendocino CPU µCode so it's likely to be supported.

1[CPU µCode in File] 🡐 SIV64X - System Information Viewer V5.84 Beta-02 RED::ray
2
3SIV64X - CPU µCode from C:\Users\ray\Downloads\VL6_7K.bin on \\RED - Windows 10 x64 Pro Workstation  V10.00  Build 19045  22H2
4
5Offset  Signature  Revision  µCode Date      Size  Flags  Processor Description
6
7039000  00000665   0003      1999-05-05       2KB  [_]10  Intel (Mendocino) [mB0]
8
9 Highlight                                ASUS WS X299 Sage BIOS 0905 03/21/2019 VROC Intel SSD Only CPU µCode 2019-04-02 (0200005E)
10
11[  OK ]  [ Copy]   [Windows]  [Machine]  [ BIOS]   [ UEFI]   [EFI Data][CPU µCode][Win µCode]

Hans Tork wrote on 2025-09-28, 15:57:

shevalier wrote on 2025-09-28, 15:13:

CPUCODE.BIN is just a file of microcodes arranged sequentially. https://github.com/platomav/CPUMicrocodes/tree/master/Intel […]
Show full quote

CPUCODE.BIN is just a file of microcodes arranged sequentially.
https://github.com/platomav/CPUMicrocodes/tree/master/Intel

Simply download the latest versions from the repository and combine them into a single file without empty spaces.
In Hexredactor, or using file merge commands in Windows CLI.
Then, using the AWARD CBRom utility, simply replace this module.
Usually for old BIOS version 1.55 is recommended.
It's not rocket science.

But, of course, first you need to get the motherboard working properly.

PS Re: Abit VL6 CPU support
For Mendocino microcode plased in noncompressed zone of BIOS.

Yeah I am now focussing on the recapping part. However I did look at using CBROM to insert microcodes(courtesy AI).

Also are there any good Socket 370 motherboards with decent caps and which are hassle free to get up and running. The ASUS board seemed good but had input issues while for this board I think I need the recapping.

If you don't mind the lack of an ISA slot, I think the Intel D815EEA/ D815EEA2 boards are usually pretty solid, stable, and hassle free. They just lack the character and tempestuousness of Abit, Asus, and the gang.

sunkindly wrote on 2025-09-28, 17:47:

Hans Tork wrote on 2025-09-28, 15:57:

shevalier wrote on 2025-09-28, 15:13:

CPUCODE.BIN is just a file of microcodes arranged sequentially. https://github.com/platomav/CPUMicrocodes/tree/master/Intel […]
Show full quote

CPUCODE.BIN is just a file of microcodes arranged sequentially.
https://github.com/platomav/CPUMicrocodes/tree/master/Intel

Simply download the latest versions from the repository and combine them into a single file without empty spaces.
In Hexredactor, or using file merge commands in Windows CLI.
Then, using the AWARD CBRom utility, simply replace this module.
Usually for old BIOS version 1.55 is recommended.
It's not rocket science.

But, of course, first you need to get the motherboard working properly.

PS Re: Abit VL6 CPU support
For Mendocino microcode plased in noncompressed zone of BIOS.

Yeah I am now focussing on the recapping part. However I did look at using CBROM to insert microcodes(courtesy AI).

Also are there any good Socket 370 motherboards with decent caps and which are hassle free to get up and running. The ASUS board seemed good but had input issues while for this board I think I need the recapping.

If you don't mind the lack of an ISA slot, I think the Intel D815EEA/ D815EEA2 boards are usually pretty solid, stable, and hassle free. They just lack the character and tempestuousness of Abit, Asus, and the gang.

Thanks for the suggestion. The SB AWE 64 is what led me to always picking up ISA slot boards and also from reading here that a ISA sound card is great.

Right now I will try to recap the board and if that does not work out try something like the non ISA boards.

This is most probably my final update. I changed the caps but had no luck with the board. It still powers on with the CPU fan running and even powers the video card. However I get no display output on my screen. After reading some other threads around here, it could be a bad EEPROM bios chip or failing to clear the ESCD.

I have given up on this board and moved to a Tyan S1854 which is actually working and I will posting my Win 95 build soon.

Once again thanks to the forum members for the helpful advice.

Coming back to this thread with news! Unfortunately, the board has stopped posting, it starts but it no longer posts, maybe because of one of the caps, I've already found 4 in a bad shape, I've also known about them but chose to ignore them since the board was working. Now, I've decided to buy a VL6 capacitor kit from ebay hoping I could fix it. I only need the 1000 microfarad 10v and the 2200 6.3v, and maybe it could post again. It's definitely that since it has worked for a while. I'm not going to throw it away. I've paired it with a Celeron at 1.1Ghz Coppermine since the Tualatin wasn't working and I discovered that after a while. What caps do you guys recommend? Thanks!

silv3r wrote on 2025-10-05, 10:56:

Coming back to this thread with news! Unfortunately, the board has stopped posting, it starts but it no longer posts, maybe because of one of the caps, I've already found 4 in a bad shape, I've also known about them but chose to ignore them since the board was working. Now, I've decided to buy a VL6 capacitor kit from ebay hoping I could fix it. I only need the 1000 microfarad 10v and the 2200 6.3v, and maybe it could post again. It's definitely that since it has worked for a while. I'm not going to throw it away. I've paired it with a Celeron at 1.1Ghz Coppermine since the Tualatin wasn't working and I discovered that after a while. What caps do you guys recommend? Thanks!

I am relatively new to soldering but I think any cap which has the same capacitance and equal/greater voltage would suffice. I went with a slightly better quality 2200 and 1500 caps than what I tend to use. I got them from amazon. I also saw a few ebay sellers who advertised industrial quality caps.

Unfortunately, even with the recap the motherboard starts but does not give a display with my CPU. I do not know if I had damaged the motherboard with the recapping. There was also a spot near the cpu bracket which could have got damaged due to the way socket 370 coolers have to be placed.

Hans Tork wrote on 2025-10-05, 16:59:

I am relatively new to soldering but I think any cap which has the same capacitance and equal/greater voltage would suffice. I w […]
Show full quote

silv3r wrote on 2025-10-05, 10:56:

Coming back to this thread with news! Unfortunately, the board has stopped posting, it starts but it no longer posts, maybe because of one of the caps, I've already found 4 in a bad shape, I've also known about them but chose to ignore them since the board was working. Now, I've decided to buy a VL6 capacitor kit from ebay hoping I could fix it. I only need the 1000 microfarad 10v and the 2200 6.3v, and maybe it could post again. It's definitely that since it has worked for a while. I'm not going to throw it away. I've paired it with a Celeron at 1.1Ghz Coppermine since the Tualatin wasn't working and I discovered that after a while. What caps do you guys recommend? Thanks!

I am relatively new to soldering but I think any cap which has the same capacitance and equal/greater voltage would suffice. I went with a slightly better quality 2200 and 1500 caps than what I tend to use. I got them from amazon. I also saw a few ebay sellers who advertised industrial quality caps.

Unfortunately, even with the recap the motherboard starts but does not give a display with my CPU. I do not know if I had damaged the motherboard with the recapping. There was also a spot near the cpu bracket which could have got damaged due to the way socket 370 coolers have to be placed.

Details

The attachment 2200.jpg is no longer available

I see that you still haven't purchased an ESR meter.
eBay and Amazon aren't the best places to buy low-ESR industrial capacitors.
Digikey, Mouser, and Farnell

shevalier wrote on 2025-10-06, 04:11:

I see that you still haven't purchased an ESR meter. eBay and Amazon aren't the best places to buy low-ESR industrial capacitors […]
Show full quote

Hans Tork wrote on 2025-10-05, 16:59:

I am relatively new to soldering but I think any cap which has the same capacitance and equal/greater voltage would suffice. I w […]
Show full quote

silv3r wrote on 2025-10-05, 10:56:

Coming back to this thread with news! Unfortunately, the board has stopped posting, it starts but it no longer posts, maybe because of one of the caps, I've already found 4 in a bad shape, I've also known about them but chose to ignore them since the board was working. Now, I've decided to buy a VL6 capacitor kit from ebay hoping I could fix it. I only need the 1000 microfarad 10v and the 2200 6.3v, and maybe it could post again. It's definitely that since it has worked for a while. I'm not going to throw it away. I've paired it with a Celeron at 1.1Ghz Coppermine since the Tualatin wasn't working and I discovered that after a while. What caps do you guys recommend? Thanks!

I am relatively new to soldering but I think any cap which has the same capacitance and equal/greater voltage would suffice. I went with a slightly better quality 2200 and 1500 caps than what I tend to use. I got them from amazon. I also saw a few ebay sellers who advertised industrial quality caps.

Unfortunately, even with the recap the motherboard starts but does not give a display with my CPU. I do not know if I had damaged the motherboard with the recapping. There was also a spot near the cpu bracket which could have got damaged due to the way socket 370 coolers have to be placed.

Details

The attachment 2200.jpg is no longer available

I see that you still haven't purchased an ESR meter.
eBay and Amazon aren't the best places to buy low-ESR industrial capacitors.
Digikey, Mouser, and Farnell

Actually I did get a 30 dollar capacitance meter from Amazon. However I did not use it too much. I did replace the caps you outlined and also another cap which looked bulgy to me.

I think I will probably get Digikey/Mouser caps next time. As amazon caps are quicker for me to acquire I went with that.

Hans Tork wrote on 2025-10-06, 15:13:

shevalier wrote on 2025-10-06, 04:11:

I see that you still haven't purchased an ESR meter. eBay and Amazon aren't the best places to buy low-ESR industrial capacitors […]
Show full quote

Hans Tork wrote on 2025-10-05, 16:59:

I am relatively new to soldering but I think any cap which has the same capacitance and equal/greater voltage would suffice. I went with a slightly better quality 2200 and 1500 caps than what I tend to use. I got them from amazon. I also saw a few ebay sellers who advertised industrial quality caps.

Unfortunately, even with the recap the motherboard starts but does not give a display with my CPU. I do not know if I had damaged the motherboard with the recapping. There was also a spot near the cpu bracket which could have got damaged due to the way socket 370 coolers have to be placed.

Details

The attachment 2200.jpg is no longer available

I see that you still haven't purchased an ESR meter.
eBay and Amazon aren't the best places to buy low-ESR industrial capacitors.
Digikey, Mouser, and Farnell

Actually I did get a 30 dollar capacitance meter from Amazon. However I did not use it too much. I did replace the caps you outlined and also another cap which looked bulgy to me.

I think I will probably get Digikey/Mouser caps next time. As amazon caps are quicker for me to acquire I went with that.

The ESR of the main capacitors used on the motherboard should be around 20 mOhm (0,02 Ohm) or lower.
30 mOhm at the most.
As you can see, ESR is measured in Ohms, and there is no mention of capacitance or voltage.

I've managed to fully recap my VL6 and this time works. But there's an anomaly. After booting the first time, the CPU FAN1 stopped working and I had to move the CPU fan to the other slot, which, surpringsly, works, also the one at the bottom of the board. Actually, I changed almost all the caps because I didn't have the little ones which I think are more difficult to replace. Anyway, it works, maybe not 100%, I still don't know which thing may have caused the CPU1 to stop being powered, but it's okay. Let's call it work in progress. Any ideas?

Motherboard dead fan problems,broken fan control circuitry.