maksymke wrote on 2024-02-22, 17:50:

Unfortunately there are some issues and the biggest mystery so far (but not a straight issue per se) is that I have no idea what make and model this motherboard might be...

Looks to be 386E-25MHz: https://theretroweb.com/motherboards/s/unknown-386e-25mhz
Seems like it's very similar to 386WB I have: https://stason.org/TULARC/pc/motherboards/U/U … OPTI-386WB.html

These old mobos are big and tend to suffer from cracked solder and broken vias due to flexing. Invest in a POST card if you want to diagnose such problems, the codes are easier to decipher than beeps. But since it beeps you know the CPU is running at the very least.

EDIT: Try swapping the RAM sticks around, and in general you only need one bank of 4 sticks to get the system to boot up. Always try minimal config in case of problems.

Deunan wrote on 2024-02-22, 17:58:

Looks to be 386E-25MHz: https://theretroweb.com/motherboards/s/unknown-386e-25mhz Seems like it's very similar to 386WB I have: […]
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maksymke wrote on 2024-02-22, 17:50:

Unfortunately there are some issues and the biggest mystery so far (but not a straight issue per se) is that I have no idea what make and model this motherboard might be...

Looks to be 386E-25MHz: https://theretroweb.com/motherboards/s/unknown-386e-25mhz
Seems like it's very similar to 386WB I have: https://stason.org/TULARC/pc/motherboards/U/U … OPTI-386WB.html

These old mobos are big and tend to suffer from cracked solder and broken vias due to flexing. Invest in a POST card if you want to diagnose such problems, the codes are easier to decipher than beeps. But since it beeps you know the CPU is running at the very least.

EDIT: Try swapping the RAM sticks around, and in general you only need one bank of 4 sticks to get the system to boot up. Always try minimal config in case of problems.

Looks like 386E, but mine lacks the jumpers 4 & 5, and has one 8bit slot instead of two.
Other than that seems identical
Thanks!

Ram swapped many times and tried in multiple configs. I had them out for cleaning and tested on other board - all in good shape.

Maybe its time to get one of the ISA test cards. I only have a PCI one, because all I did were late 486 boards and this is the first 386 that I got my hands on.
ALTHOUGH >from my experience< I don’t expect it to show any particular error code that would be different from what the BIOS is telling me already. I think maybe it will indicate a missing voltage? That's also a clue to follow.

maksymke wrote on 2024-02-22, 21:14:

Looks like 386E, but mine lacks the jumpers 4 & 5, and has one 8bit slot instead of two.

Good eye! But I've seen many mobos where the 8-bit slot was just a standard 16-bit one, but the edge connector was shorter. One could replace it with a standard one to gain another full size ISA slot. I think that was also the case here and you simply have the better version already.
J4 & J5 seem to be a way to switch from PSU to on-mobo power good signal - I'm not sure why that's even an option, it should always be PSU driven. And your mobo seems to have that space unpopulated but could probably be easily modified to have that functionality. Not that it's of any use.

maksymke wrote on 2024-02-22, 21:14:

Maybe its time to get one of the ISA test cards. I only have a PCI one, because all I did were late 486 boards and this is the first 386 that I got my hands on.

Well sometimes you can spot things, like missing voltages, or proper reset signal, or just the sequence of codes - which might give you a clue of some sort. For example that the mobo thinks it has MDA adapter plugged in instead of CGA/EGA/VGA, due to a glitch in the VRAM detection code. AFAIK the code you get is non-fatal and the system should continue to boot, access floppies for example. If the POST card shows no codes at all, you can suspect a general failure with ISA bus drivers - see that '245 right next to battery? It often dies, or gets damaged by some card (often just one bit is affected).

Based on the 8 beeps. You could try cleaning the ISA slots with Isopropyl alcohol & a toothbrush. Reinsert the card multiple times. Try different slots.

Also use a multimeter on all the traces near the battery, from start to finish. One of the vias on the top right of the board looks green/non conductive - it may not send data through to the other side.

MikeSG wrote on 2024-02-23, 06:49:

Based on the 8 beeps. You could try cleaning the ISA slots with Isopropyl alcohol & a toothbrush. Reinsert the card multiple times. Try different slots.

Also use a multimeter on all the traces near the battery, from start to finish. One of the vias on the top right of the board looks green/non conductive - it may not send data through to the other side.

Done and done and done

And done - all the traces are tested and conductive through both sides. It looks bad, but it’s good
All the ISA pins are also conductive and connect where they should and between each other

Deunan wrote on 2024-02-22, 22:15:

Well sometimes you can spot things, like missing voltages, or proper reset signal, or just the sequence of codes - which might give you a clue of some sort. For example that the mobo thinks it has MDA adapter plugged in instead of CGA/EGA/VGA, due to a glitch in the VRAM detection code. AFAIK the code you get is non-fatal and the system should continue to boot, access floppies for example. If the POST card shows no codes at all, you can suspect a general failure with ISA bus drivers - see that '245 right next to battery? It often dies, or gets damaged by some card (often just one bit is affected).

I’ll just wait for the test card to arrive and then we’ll proceed.

That chip also may be the lead. I can see that it’s dirt cheap and easily replaceable and I really hope it just might be the case. I’m going to inspect it out of the board right away.

It's cheap but you want ALS245 and not anything else. ACT might be a good substitute but the more common HCT can be too slow or have to low drive for all these ISA slots.
Also it should be safe-ish to try and piggy-back the original chip with a brand new one of the same series. I would not expect any problems, except maybe the new chip to also get damaged (but that shouldn't happen instantly). Piggy-back won't always reveal the cause but it's easy to try before you commit to desolering. And if you do then put a socket in there rather than soldering another '245 directly, just in case another one eventually dies due to some short on the ISA slots or something.