evanboonie wrote on 2025-11-01, 23:04:

Chkcpu wrote on 2025-02-27, 19:55:

Hi evanboonie, […]
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Hi evanboonie,

That is quite a challenge you have there, getting a K6-2 to run on the Apple 1997 PC Compatibility Card!

Looking into the AMI BIOS9.ROM, I see this card uses the OPTi 557M Viper-M chipset. This is a 1995 chipset for socket 5 boards. But the BIOS9.ROM looks like it is from 1997 and it has the expected CPU support from that era: Intel Pentium and Pentium MMX, Cyrix 6x86 and 6x86MX, and AMD K5 and K6. So no support for any IDT WinChip.

The K6 support in this BIOS is only for the original K6 model 6, the 2.9V/3.2V Vcore models. The 2.2V K6 model 7 and all later K6(-2/III) models are not supported.

If your K6-233 is a 3.2V model 6, it is supported by the BIOS. But the BIOS also contains an Apple Compatibility BIOS v1.6.4 module that may prevent other than the original Pentium from running.
Although I’m just guessing here, it would be interesting to see if a Pentium MMX, Cx686MX, or AMD K5 work on this card. If you have one of these CPUs, please try.

Another issue may be the power supply. The K6-233 draws a lot more current than a Pentium 166/200. If you can lower the multiplier, you could test the K6-233 at 200 or 166MHz. At these speeds, this CPU will run fine at a lower 2.9V Vcore.

Now to answer your question, with basic K6 support it should be possible to add K6-2 support to this BIOS. But this is a lot of work, so please try the above CPU alternates first, so I know that the time spent on patching this BIOS is not waisted. 😉

Cheers, Jan

Jan, I have finally gotten around to testing the K6-233 again with an externally powered voltage adapter and I'm pleased to report that it worked! So it does appear that the K6 was just a little too power hungry for the built-in regulator. I also realized that I gave you the modded BIOS file (BIOS9.ROM) which I had attempted to replace the VBIOS module using amibcp. It is likely best to start any CPU additions on the base BIOS and I should be able to easily add my VBIOS and second cache bank mods on top of that if it works. The original BIOS I have attached here (BIOS 8.bios) is the file exactly as I extracted it from the Mac application.

Hi evanboonie,

Nice to hear that the K6-233 works fine now via that voltage adapter, and thanks for uploading the original BIOS8.ROM.

It took me a while, but I’ve just started disassembling this BIOS to see what needs to be changed for K6-2(+)/III(+) support. This is the oldest AMI BIOS I’ve ever patched, so I don’t know yet if I’m able to add this CPU support.
I’ll let you know what I find.

Cheers, Jan

I know this is well past your usual expertise, but got any thoughts?

I am pretty sure I'm on the right track with this AMI bios setting the superio registers, but maybe I'm reading the datasheet wrong.
There are a few in red in the attached spreadsheet I can't make sense of.

https://www.electronicsdatasheets.com/manufac … k/parts/f71889f

myne wrote on 2025-12-04, 15:25:

I know this is well past your usual expertise, but got any thoughts? […]
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I know this is well past your usual expertise, but got any thoughts?

I am pretty sure I'm on the right track with this AMI bios setting the superio registers, but maybe I'm reading the datasheet wrong.
There are a few in red in the attached spreadsheet I can't make sense of.

https://www.electronicsdatasheets.com/manufac … k/parts/f71889f

Hi myne,

You did a fine analysis of the register programming on this F71889 Super I/O chip.
The register or bit definitions your marked unknown in your spreadsheet are indeed not defined in the datasheet.

The version of this F71889 datasheet is from April 2010 and if your BIOS is from a later date, there are bound to be some discrepancies.
I see this a lot in older 1994-2000 BIOSes as well, when I compare chipset and peripheral register programming with the datasheets at hand.
This discrepancy can be caused by either:
1) The chip is from a later revision and not completely covered by the available datasheet, or
2) The undefined register or bit definition is left out on purpose. These undocumented definitions may then be supplied to BIOS vendors and board manufacturers only, under a non-disclosure agreement.

The reason to keep some definitions undocumented is anybody’s guess. Maybe a patent was still pending, or the undocumented function was only needed to correct the chips behavior under specific conditions.

Cheers, Jan

Ahhhh. Thanks.

So I'm definitely on the right track?

It actually seems simpler than I expected.
It's always 1 command and 1 setting.

It's not far off a normal gui menu.
Select tools, select options,
Select device turn on x.
Select file, click save.

There were a couple of red ones i think I got right, but I'm not sure about. Was i right?

myne wrote on 2025-12-04, 23:05:

There were a couple of red ones i think I got right, but I'm not sure about. Was i right?

Yes, I’ve looked at the red definitions in your F71889 spreadsheet.

LDN CR04 (Hardware Monitor Device Configuration)
- Register offsets F0h and F1h are undocumented, and both are programmed with the value 10h. I have no idea where these registers are for.

LDN CR06 (GPIO Device Configuration)
- Here, a long list of registers is programmed to setup all these General Purpose I/O lines. I see a repeating pattern in the definitions of these registers, only B3h is missing in the datasheet. Looking at the definition of other x3h registers from F3h to 83h on page 62-63, I believe B3h is “GPIO4 Drive Enable register”. Probably just an omission from the datasheet.
Register A0h is documented on page 63 as “GPIO5 Output Enable register”.
Register FEh is documented as “LED_VSB Control register”.
Register FFh is documented as “LED_VCC Control register”.

Hope this helps.
Jan

Cheers.

Any idea if there's something like a register table for the chipsets in amibios8?
Ie here's the bios defaults, just blindly copy them all to the chipset?

myne wrote on 2025-12-08, 02:23:

Cheers.

Any idea if there's something like a register table for the chipsets in amibios8?
Ie here's the bios defaults, just blindly copy them all to the chipset?

Hi myne,

I’m not sure if I understand your question and what you are trying to do, please elaborate.
Can you also tell which BIOS you are working on and what version of AMIBCP you are using? Then I should be able to give you a more direct answer. 😉

Cheers, Jan

I just mean a single table or string that contains all the chipset register data - including the ones that aren't in the bios setup

Is there such a thing?

I'm looking at the msi g41m-e43
https://www.msi.com/Motherboard/g41m-e43/support

myne wrote on 2025-12-09, 07:50:

I just mean a single table or string that contains all the chipset register data - including the ones that aren't in the bios se […]
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I just mean a single table or string that contains all the chipset register data - including the ones that aren't in the bios setup

Is there such a thing?

I'm looking at the msi g41m-e43
https://www.msi.com/Motherboard/g41m-e43/support

When I want to look at the chipset registers data, after the BIOS and Windows have done their setup job, I use the well-known CPUID tool CPUZ.
https://www.cpuid.com/softwares/cpu-z.html

Under the About tab, you’ll find a Save Report (.TXT) button that generates an extensive system report which includes a raw register dump of the configuration space of each PCI device in the system.

This is not exactly a table or string of register data, but because the report is a text-file you can edit it easily to your liking.

Jan

PC@LIVE wrote on 2025-11-21, 10:08:

Ciao Jan, excuse me but I noticed now that you can send the copy of the BIOS to TRW, I wanted to ask you if you can also send th […]
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Chkcpu wrote on 2025-11-20, 19:16:

Ciao Elio, […]
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PC@LIVE wrote on 2025-11-20, 12:00:

Ciao Jan
Excuse me, I just wanted to let you know that I put two BIOS files, in my MB test and troubleshooting page, they are in txt format, but in reality they are bins, one is from the MB PINE PT-2068.1 and the other from the ISA WD90C00 video card.

Ciao Elio,

Thanks for letting me know about these BIOS files.
The WD20D90 video card BIOS looks fine and has a correct checksum.

The PINE PT-2068.1 / PowerTech MB457 BIOS however is corrupted. ….

When able, put this new BIOS copy on your MB test and troubleshooting page, and I will check it for you so we can send it to TRW.

Cheers, Jan

Ciao Jan, excuse me but I noticed now that you can send the copy of the BIOS to TRW, I wanted to ask you if you can also send the manual files, because there is nothing in the documentation.
Maybe someone would need them for the correct setting of the jumpers, unfortunately I can't access, if you can do it for me.
Thank you Regards

Ciao Elio,

I have some news about the 02/07/95 BIOS from your PINE PT-2068.1 / PowerTech MB457 board.
The BIOS dump you posted in your PC@LIVE thread was a shadow RAM copy and has checksum errors. I have been analyzing this BIOS and found out where the BIOS changed several bytes and a checksum in shadow RAM, to store Power Management and Harddisk data.

I was able to reverse these changes in your shadow RAM copy, so I got the original BIOS ROM copy back, as stored in the EPROM on your board. 😀

Here is this 02/07/95-UMC-498GP-2C4X6000-00 Ver. PT-2068.1 BIOS.

You can use this as your BIOS backup file, and I will send it to TRW as well.

If you have scans of the motherboard manual, please post them here so I can send them to TRW as well.

Buon Natale, Jan

Chkcpu wrote on 2025-12-21, 16:28:

Ciao Elio, […]
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PC@LIVE wrote on 2025-11-21, 10:08:

Ciao Jan, excuse me but I noticed now that you can send the copy of the BIOS to TRW, I wanted to ask you if you can also send th […]
Show full quote

Chkcpu wrote on 2025-11-20, 19:16:

Ciao Elio, […]
Show full quote

Ciao Elio,

Thanks for letting me know about these BIOS files.
The WD20D90 video card BIOS looks fine and has a correct checksum.

The PINE PT-2068.1 / PowerTech MB457 BIOS however is corrupted. ….

When able, put this new BIOS copy on your MB test and troubleshooting page, and I will check it for you so we can send it to TRW.

Cheers, Jan

Ciao Jan, excuse me but I noticed now that you can send the copy of the BIOS to TRW, I wanted to ask you if you can also send the manual files, because there is nothing in the documentation.
Maybe someone would need them for the correct setting of the jumpers, unfortunately I can't access, if you can do it for me.
Thank you Regards

Ciao Elio,

I have some news about the 02/07/95 BIOS from your PINE PT-2068.1 / PowerTech MB457 board.
The BIOS dump you posted in your PC@LIVE thread was a shadow RAM copy and has checksum errors. I have been analyzing this BIOS and found out where the BIOS changed several bytes and a checksum in shadow RAM, to store Power Management and Harddisk data.

I was able to reverse these changes in your shadow RAM copy, so I got the original BIOS ROM copy back, as stored in the EPROM on your board. 😀

Here is this 02/07/95-UMC-498GP-2C4X6000-00 Ver. PT-2068.1 BIOS.

The attachment PT2068_1.zip is no longer available

You can use this as your BIOS backup file, and I will send it to TRW as well.

If you have scans of the motherboard manual, please post them here so I can send them to TRW as well.

Buon Natale, Jan

Ciao Jan,
Thank you very much for fixing the BIOS of the Pine PT-2068.1, in fact I had tried to create a backup copy, but I didn't know that it could be modified by that program, however yes I have images of the manual, basically it's only 4 pages, but it's enough to select the few jumpers, present on the motherboard, I'll add them here.
Thank you, Merry Christmas 🎄 to you too

Hi all!

Currently i try to hi-tune rare PCI-VLB-ISA Socket5 motherboard - Spring Circle SF586 (Forex chipset)

As a part of my "project" i try to understand and tune AWARD BIOS 4.50 for it. I edit it to more nice cosmetics and ensble some hidden options in PCI section.

Are there any chances to patch Y2K bug and add more advanced IDE LBA support (currently it detects up to 1.8GB disk capacity only).?

Will try to find WinChip (2) later but as i understand there only Intel Pentium-S support only?

Babasha wrote on 2025-12-23, 22:06:

Hi all! […]
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Hi all!

Currently i try to hi-tune rare PCI-VLB-ISA Socket5 motherboard - Spring Circle SF586 (Forex chipset)

As a part of my "project" i try to understand and tune AWARD BIOS 4.50 for it. I edit it to more nice cosmetics and ensble some hidden options in PCI section.

Are there any chances to patch Y2K bug and add more advanced IDE LBA support (currently it detects up to 1.8GB disk capacity only).?

Will try to find WinChip (2) later but as i understand there only Intel Pentium-S support only?

Hi Babasha,

I’ve looked at your tuned-up Award v4.50G BIOS from the SF586 board.
Interesting BIOS which is mainly still uncompressed.

I’ve made two changes:
1) I’ve changed the minimum date from 1-1-1994 to 1-1-2000. The maximum date was already 31-12-2099, so the BIOS will now only accept dates from 1-1-2000 to 31-12-2099. This should fix both the Y2K and Year2094 bugs.

2) I’ve fixed the 2GB Harddisk display limit bug, to allow drives up to 8GB to be recognized. This 8GB is the drive limit of this BIOS.

I’ve named this adjusted BIOS “BABASHA1.BIN”.

Let us know if this fixes these issues.

The CPU support in this BIOS is indeed very limited. I only see Pentium (P54) and Cyrix 6x86 (M1) support. No Pentium MMX, Cx6x86MX, K5, K6, or Winchip C6/2 support.
I don’t know if Winchip support can be added. I need to disassemble and analyze the BIOS for that and this takes time. I expect to have time for that in a month.

Cheers, Jan

Chkcpu wrote on 2025-12-24, 19:36:

Hi Babasha, […]
Show full quote

Babasha wrote on 2025-12-23, 22:06:

Hi all! […]
Show full quote

Hi all!

Currently i try to hi-tune rare PCI-VLB-ISA Socket5 motherboard - Spring Circle SF586 (Forex chipset)

As a part of my "project" i try to understand and tune AWARD BIOS 4.50 for it. I edit it to more nice cosmetics and ensble some hidden options in PCI section.

Are there any chances to patch Y2K bug and add more advanced IDE LBA support (currently it detects up to 1.8GB disk capacity only).?

Will try to find WinChip (2) later but as i understand there only Intel Pentium-S support only?

Hi Babasha,

I’ve looked at your tuned-up Award v4.50G BIOS from the SF586 board.
Interesting BIOS which is mainly still uncompressed.

I’ve made two changes:
1) I’ve changed the minimum date from 1-1-1994 to 1-1-2000. The maximum date was already 31-12-2099, so the BIOS will now only accept dates from 1-1-2000 to 31-12-2099. This should fix both the Y2K and Year2094 bugs.

2) I’ve fixed the 2GB Harddisk display limit bug, to allow drives up to 8GB to be recognized. This 8GB is the drive limit of this BIOS.

I’ve named this adjusted BIOS “BABASHA1.BIN”.

The attachment BABASHA1.zip is no longer available

Let us know if this fixes these issues.

The CPU support in this BIOS is indeed very limited. I only see Pentium (P54) and Cyrix 6x86 (M1) support. No Pentium MMX, Cx6x86MX, K5, K6, or Winchip C6/2 support.
I don’t know if Winchip support can be added. I need to disassemble and analyze the BIOS for that and this takes time. I expect to have time for that in a month.

Cheers, Jan

Tnx for your help and comments.
Will flash it in friday and check what we get.

Chkcpu wrote on 2025-12-24, 19:36:

Hi Babasha, […]
Show full quote

Babasha wrote on 2025-12-23, 22:06:

Hi all! […]
Show full quote

Hi all!

Currently i try to hi-tune rare PCI-VLB-ISA Socket5 motherboard - Spring Circle SF586 (Forex chipset)

As a part of my "project" i try to understand and tune AWARD BIOS 4.50 for it. I edit it to more nice cosmetics and ensble some hidden options in PCI section.

Are there any chances to patch Y2K bug and add more advanced IDE LBA support (currently it detects up to 1.8GB disk capacity only).?

Will try to find WinChip (2) later but as i understand there only Intel Pentium-S support only?

Hi Babasha,

I’ve looked at your tuned-up Award v4.50G BIOS from the SF586 board.
Interesting BIOS which is mainly still uncompressed.

I’ve made two changes:
1) I’ve changed the minimum date from 1-1-1994 to 1-1-2000. The maximum date was already 31-12-2099, so the BIOS will now only accept dates from 1-1-2000 to 31-12-2099. This should fix both the Y2K and Year2094 bugs.

2) I’ve fixed the 2GB Harddisk display limit bug, to allow drives up to 8GB to be recognized. This 8GB is the drive limit of this BIOS.

I’ve named this adjusted BIOS “BABASHA1.BIN”.

The attachment BABASHA1.zip is no longer available

Let us know if this fixes these issues.

The CPU support in this BIOS is indeed very limited. I only see Pentium (P54) and Cyrix 6x86 (M1) support. No Pentium MMX, Cx6x86MX, K5, K6, or Winchip C6/2 support.
I don’t know if Winchip support can be added. I need to disassemble and analyze the BIOS for that and this takes time. I expect to have time for that in a month.

Cheers, Jan

Once more time - TNX FOR YOUR GREAT HELP!

BIOS B26.1 (your version) successfully detects my 8GB HDD and translates date from 31-12-1999 to 01-01-2000
SPEEDSYS still warns about Y2K BUG 1999-1900 but i think its RTC bug (not BIOS) and BIOS patches it with transfer to 2000?

Chkcpu wrote on 2025-12-21, 16:28:

Ciao Elio, […]
Show full quote

PC@LIVE wrote on 2025-11-21, 10:08:

Ciao Jan, excuse me but I noticed now that you can send the copy of the BIOS to TRW, I wanted to ask you if you can also send th […]
Show full quote

Chkcpu wrote on 2025-11-20, 19:16:

Ciao Elio, […]
Show full quote

Ciao Elio,

Thanks for letting me know about these BIOS files.
The WD20D90 video card BIOS looks fine and has a correct checksum.

The PINE PT-2068.1 / PowerTech MB457 BIOS however is corrupted. ….

When able, put this new BIOS copy on your MB test and troubleshooting page, and I will check it for you so we can send it to TRW.

Cheers, Jan

Ciao Jan, excuse me but I noticed now that you can send the copy of the BIOS to TRW, I wanted to ask you if you can also send the manual files, because there is nothing in the documentation.
Maybe someone would need them for the correct setting of the jumpers, unfortunately I can't access, if you can do it for me.
Thank you Regards

Ciao Elio,

I have some news about the 02/07/95 BIOS from your PINE PT-2068.1 / PowerTech MB457 board.
The BIOS dump you posted in your PC@LIVE thread was a shadow RAM copy and has checksum errors. I have been analyzing this BIOS and found out where the BIOS changed several bytes and a checksum in shadow RAM, to store Power Management and Harddisk data.

I was able to reverse these changes in your shadow RAM copy, so I got the original BIOS ROM copy back, as stored in the EPROM on your board. 😀

Here is this 02/07/95-UMC-498GP-2C4X6000-00 Ver. PT-2068.1 BIOS.

The attachment PT2068_1.zip is no longer available

You can use this as your BIOS backup file, and I will send it to TRW as well.

If you have scans of the motherboard manual, please post them here so I can send them to TRW as well.

Buon Natale, Jan

Ciao Jan
Thank you so much for fixing the MB PINE PT-2068.1 file.
I just finished rewriting the BIOS chip on the ASUS K8U-X that I'm trying to get working. After a few boot tests, it displayed a screen for Boot Block via floppy.
I used a different technique, using Nano USB Programmer. I wrote the latest version, but first I saved the one that had problems. I'm attaching the file here, and I warn anyone that that file could be corrupted, so I don't recommend using it.
I hope you find useful information in that file. If you'd like to see it, I'll post an update soon on my Test page here on Vogons.
Best regards

PC@LIVE wrote on 2025-12-27, 15:55:

Ciao Jan Thank you so much for fixing the MB PINE PT-2068.1 file. I just finished rewriting the BIOS chip on the ASUS K8U-X that […]
Show full quote

Chkcpu wrote on 2025-12-21, 16:28:

Ciao Elio, […]
Show full quote

PC@LIVE wrote on 2025-11-21, 10:08:

Ciao Jan, excuse me but I noticed now that you can send the copy of the BIOS to TRW, I wanted to ask you if you can also send the manual files, because there is nothing in the documentation.
Maybe someone would need them for the correct setting of the jumpers, unfortunately I can't access, if you can do it for me.
Thank you Regards

Ciao Elio,

I have some news about the 02/07/95 BIOS from your PINE PT-2068.1 / PowerTech MB457 board.
The BIOS dump you posted in your PC@LIVE thread was a shadow RAM copy and has checksum errors. I have been analyzing this BIOS and found out where the BIOS changed several bytes and a checksum in shadow RAM, to store Power Management and Harddisk data.

I was able to reverse these changes in your shadow RAM copy, so I got the original BIOS ROM copy back, as stored in the EPROM on your board. 😀

Here is this 02/07/95-UMC-498GP-2C4X6000-00 Ver. PT-2068.1 BIOS.

The attachment PT2068_1.zip is no longer available

You can use this as your BIOS backup file, and I will send it to TRW as well.

If you have scans of the motherboard manual, please post them here so I can send them to TRW as well.

Buon Natale, Jan

Ciao Jan
Thank you so much for fixing the MB PINE PT-2068.1 file.
I just finished rewriting the BIOS chip on the ASUS K8U-X that I'm trying to get working. After a few boot tests, it displayed a screen for Boot Block via floppy.
I used a different technique, using Nano USB Programmer. I wrote the latest version, but first I saved the one that had problems. I'm attaching the file here, and I warn anyone that that file could be corrupted, so I don't recommend using it.
I hope you find useful information in that file. If you'd like to see it, I'll post an update soon on my Test page here on Vogons.
Best regards

Ciao Elio,

I’ve checked the K8UX-EX BIOS, and it is identical to the K8UX0703 BIOS from TRW.
So the problems you have with this board are not caused by a corrupted BIOS.

It is good that you programmed the latest 1001 BIOS into the flash chip now, but there must be another failure on the board.
Because you get a bootblock recovery message while the BIOS is good, this usually means a memory problem. Please check the RAM, the DIMM slots contacts, and the traces between the DIMM slots and the CPU socket.

Greetings, Jan

Chkcpu wrote on 2025-12-27, 17:56:

Ciao Elio, […]
Show full quote

PC@LIVE wrote on 2025-12-27, 15:55:

Ciao Jan Thank you so much for fixing the MB PINE PT-2068.1 file. I just finished rewriting the BIOS chip on the ASUS K8U-X that […]
Show full quote

Chkcpu wrote on 2025-12-21, 16:28:

Ciao Elio, […]
Show full quote

Ciao Elio,

I have some news about the 02/07/95 BIOS from your PINE PT-2068.1 / PowerTech MB457 board.
The BIOS dump you posted in your PC@LIVE thread was a shadow RAM copy and has checksum errors. I have been analyzing this BIOS and found out where the BIOS changed several bytes and a checksum in shadow RAM, to store Power Management and Harddisk data.

I was able to reverse these changes in your shadow RAM copy, so I got the original BIOS ROM copy back, as stored in the EPROM on your board. 😀

Here is this 02/07/95-UMC-498GP-2C4X6000-00 Ver. PT-2068.1 BIOS.

The attachment PT2068_1.zip is no longer available

You can use this as your BIOS backup file, and I will send it to TRW as well.

If you have scans of the motherboard manual, please post them here so I can send them to TRW as well.

Buon Natale, Jan

Ciao Jan
Thank you so much for fixing the MB PINE PT-2068.1 file.
I just finished rewriting the BIOS chip on the ASUS K8U-X that I'm trying to get working. After a few boot tests, it displayed a screen for Boot Block via floppy.
I used a different technique, using Nano USB Programmer. I wrote the latest version, but first I saved the one that had problems. I'm attaching the file here, and I warn anyone that that file could be corrupted, so I don't recommend using it.
I hope you find useful information in that file. If you'd like to see it, I'll post an update soon on my Test page here on Vogons.
Best regards

Ciao Elio,

I’ve checked the K8UX-EX BIOS, and it is identical to the K8UX0703 BIOS from TRW.
So the problems you have with this board are not caused by a corrupted BIOS.

It is good that you programmed the latest 1001 BIOS into the flash chip now, but there must be another failure on the board.
Because you get a bootblock recovery message while the BIOS is good, this usually means a memory problem. Please check the RAM, the DIMM slots contacts, and the traces between the DIMM slots and the CPU socket.

Greetings, Jan

Ciao, Jan
So I can confirm what you wrote, unfortunately the BIOS update did not solve the problem, which remained more or less the same, undoubtedly there is a problem (HW?), all the RAM tested do not show progress, and the codes are usually the same, in short I will try it with another 754 motherboard, so as to find reliably working RAM, and I will try the Sempron 3000 CPU, if everything is working, I will try to check the welds of the RAM banks, maybe there could be some non-optimal contact.
Greetings

Chkcpu wrote on 2025-12-24, 19:36:

Hi Babasha, […]
Show full quote

Babasha wrote on 2025-12-23, 22:06:

Hi all! […]
Show full quote

Hi all!

Currently i try to hi-tune rare PCI-VLB-ISA Socket5 motherboard - Spring Circle SF586 (Forex chipset)

As a part of my "project" i try to understand and tune AWARD BIOS 4.50 for it. I edit it to more nice cosmetics and ensble some hidden options in PCI section.

Are there any chances to patch Y2K bug and add more advanced IDE LBA support (currently it detects up to 1.8GB disk capacity only).?

Will try to find WinChip (2) later but as i understand there only Intel Pentium-S support only?

Hi Babasha,

I’ve looked at your tuned-up Award v4.50G BIOS from the SF586 board.
Interesting BIOS which is mainly still uncompressed.

I’ve made two changes:
1) I’ve changed the minimum date from 1-1-1994 to 1-1-2000. The maximum date was already 31-12-2099, so the BIOS will now only accept dates from 1-1-2000 to 31-12-2099. This should fix both the Y2K and Year2094 bugs.

2) I’ve fixed the 2GB Harddisk display limit bug, to allow drives up to 8GB to be recognized. This 8GB is the drive limit of this BIOS.

I’ve named this adjusted BIOS “BABASHA1.BIN”.

The attachment BABASHA1.zip is no longer available

Let us know if this fixes these issues.

The CPU support in this BIOS is indeed very limited. I only see Pentium (P54) and Cyrix 6x86 (M1) support. No Pentium MMX, Cx6x86MX, K5, K6, or Winchip C6/2 support.
I don’t know if Winchip support can be added. I need to disassemble and analyze the BIOS for that and this takes time. I expect to have time for that in a month.

Cheers, Jan

Hi!
One more idea

If you will disassemble BIOS - can you look in external BIOS of ISA/PCI cards detection
I think it works with 16 or 32KB BIOS extensions only but maybe it can be patched up to 64KB?
My friend get success with that on his FIC 486-VIP0IO2 with same

THANK YOU ANYWAY!

Hello all
I have the same bug with my bios but still couldn't apply the fix.
Is it possible to help me with that

https://theretroweb.com/motherboards/639