I tried the GA-586UX BIOS on several HX mainboards (same super I/O etc.) but it never worked.

On the 586DX the 1st of the PCI-slots shares IRQ with the onboard SCSI chip even if onboard SCSI is disabled.
The last PCI-slot is "slave only" and restricted to add on cards that comply with this (virtually none).

So even when onboard SCSI is used (which is a good idea anyway) and video and ISA PNP sound are present adding a NIC gets you into trouble. WIndows 2000 manages to solve the problems, but under NT 4.0 that I´m running on this board, I couldn´t find a way to run any(!) NIC - ISA or PCI - 100% stable so far.
As soon as large files are transmitted the NIC will fail to work after some time.

majestyk wrote on 2023-03-17, 06:40:

I tried the GA-586UX BIOS on several HX mainboards (same super I/O etc.) but it never worked. […]
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I tried the GA-586UX BIOS on several HX mainboards (same super I/O etc.) but it never worked.

On the 586DX the 1st of the PCI-slots shares IRQ with the onboard SCSI chip even if onboard SCSI is disabled.
The last PCI-slot is "slave only" and restricted to add on cards that comply with this (virtually none).

So even when onboard SCSI is used (which is a good idea anyway) and video and ISA PNP sound are present adding a NIC gets you into trouble. WIndows 2000 manages to solve the problems, but under NT 4.0 that I´m running on this board, I couldn´t find a way to run any(!) NIC - ISA or PCI - 100% stable so far.
As soon as large files are transmitted the NIC will fail to work after some time.

Have you tried the modified bios from Jan?
Yo have troubles even when using isa slots for both audio and Nic?
I do not plan to use the scsi controller because of the 8GB limitation. So one pci will be used for an ata100 card as it seems there is no other solution.

Will do.
Maybe IRQ routing can be optimized manually this way.

majestyk wrote on 2023-03-17, 07:03:

Will do.
Maybe IRQ routing can be optimized manually this way.

Please report!
Be advised, the bios is for 2A revision.
Not sure it can harm as I am using the 3.43 and the difference is on the better multiplier handling and the raid port (apart from the absence of usb headers)

Here is the 3.43 version with all options enabled:

majestyk wrote on 2023-03-17, 09:31:

Here is the 3.43 version with all options enabled:
5DXA.7z

Great,
Did you test it? Any improvement?
8GB limitation still there?

majestyk wrote on 2023-03-17, 09:31:

Here is the 3.43 version with all options enabled:
5DXA.7z

Tested the 2.40, all ok but the usb seems to be still disabled, even if during post the controller is visible and with an assigned IRQ.
I really do not understand.
Maybe the pinout is proprietary?
I fail to find a scheme.

I would recommend don´t use the chipset USB here, all the EV protection components are missing. One static discharge / surge at the USB connector and the southbridge can be toast.
My 3.43 is running fine but I havent found the time to experiment with different IRQ settings yet.

majestyk wrote on 2023-03-17, 17:01:

I would recommend don´t use the chipset USB here, all the EV protection components are missing. One static discharge / surge at the USB connector and the southbridge can be toast.
My 3.43 is running fine but I havent found the time to experiment with different IRQ settings yet.

I can agree, but I do not see a better circuitry on ga-586… boards that have functional usb.
In any case, if IRQ routing is better would be paramount.

I am waiting for a 40 pole cable to install win2000 on it, incredibly I have ultraATA cables only and my sata adapter won’t work with this board.

majestyk wrote on 2023-03-17, 17:01:

I would recommend don´t use the chipset USB here, all the EV protection components are missing. One static discharge / surge at the USB connector and the southbridge can be toast.
My 3.43 is running fine but I havent found the time to experiment with different IRQ settings yet.

Any update?

Hi.
I have such a board, the manufacturer is unknown, for the SUNTAC ST62C303-A chipset. I found a very similar one in the database, I noticed that there is no BIOS. I made the "AWARD V3.1c" damper. I don't know if it's the same board, mine has more chips. I am asking Admin to verify and add to the database.
https://theretroweb.com/motherboards/s/unknow … -286p#downloads

Regards, AdrianD

Actually, your board is not missing any chips. I have renamed the page since we now have a manufacturer name
https://theretroweb.com/motherboards/s/protech-suntac-286p

I just got ALR JUGA1486 system based on ALR EXPRESS VL platform.
Like on most brand PC's of 90's BIOS SETUP utility moved to hard drive. Is there any way to recover SETUP form hard drive and then reuse it on other hard drives?