PC Hoarder Patrol wrote on 2024-05-18, 13:35:

jnemo2004 wrote on 2024-05-18, 06:59:

Hello!, good morning.
I would like to find any info about this motherboard: OP3486H
Thank you and regards.

Don't see it on The Retro Web (might be worth submitting here https://theretroweb.com/info/contributions ), but possibly this from The PC Engineers Reference Book...

Unknown (OP)3486.jpg

Hello good morning. Here are some photos of the motherboard. I know they are not of very good quality but I don't have a better camera. In a few days I will remove the ICs that are in socket to wash the board and then I will dump the BIOS and leave it here as well. Please post the photos of the board on The Retro Web as I do not have the experience to do so.
Thank you so much

Perhaps Opti's Local Bus, seeing the chipset is theirs. Not much standard back then.

(I recall a friend imported some local bus mobos + local bus video cards from the same chinese company, and then they didn't work together.
When he asked about it, he just got a 'sorry, hope it's not a problem for you' from the guys...last purchase made there.)

jnemo2004 wrote on 2024-05-19, 08:12:

PC Hoarder Patrol wrote on 2024-05-18, 13:35:

jnemo2004 wrote on 2024-05-18, 06:59:

Hello!, good morning.
I would like to find any info about this motherboard: OP3486H
Thank you and regards.

Don't see it on The Retro Web (might be worth submitting here https://theretroweb.com/info/contributions ), but possibly this from The PC Engineers Reference Book...

Unknown (OP)3486.jpg

Hello good morning. Here are some photos of the motherboard. I know they are not of very good quality but I don't have a better camera. In a few days I will remove the ICs that are in socket to wash the board and then I will dump the BIOS and leave it here as well. Please post the photos of the board on The Retro Web as I do not have the experience to do so.
Thank you so much

Thanks for the pics...as requested I'll pass them on to the RTW team for inclusion though, after a more detailed check, it would appear your board is already there - https://theretroweb.com/motherboards/s/zida-opti-3486

PC Hoarder Patrol wrote on 2024-05-20, 07:18:

jnemo2004 wrote on 2024-05-19, 08:12:

PC Hoarder Patrol wrote on 2024-05-18, 13:35:

Don't see it on The Retro Web (might be worth submitting here https://theretroweb.com/info/contributions ), but possibly this from The PC Engineers Reference Book...

Unknown (OP)3486.jpg

Hello good morning. Here are some photos of the motherboard. I know they are not of very good quality but I don't have a better camera. In a few days I will remove the ICs that are in socket to wash the board and then I will dump the BIOS and leave it here as well. Please post the photos of the board on The Retro Web as I do not have the experience to do so.
Thank you so much

Thanks for the pics...as requested I'll pass them on to the RTW team for inclusion though, after a more detailed check, it would appear your board is already there - https://theretroweb.com/motherboards/s/zida-opti-3486

Thank you very, very much.

Hello, here you have the BIOS dump.
Regards.

About the math coprocessor 3C87-40
Is it correctly mounted in the socket? I believe, it is not.
Thank you

https://www.cpu-world.com/CPUs/80387/IIT-3C87-25.html

I'd expect that pin 1 would be indicated with the little corner stud, by the sticker. And the silkscreen on bottom right matches the PGA holder, so you may be right that it is misaligned - maybe broken, if powered on in that position...try to verify comparing locations of the ground pins perhaps?

I didn´t happen very often, but when I happened to insert a 5V CPU the wrong way it shorted the 5V rail so the PSU wouldn´t start.
It wouuldn´t surprise me if the same goes for FPUs.

Hey all, thanks in advance for taking the time to read and reply

I recently came into a few Gateway 2000 computers and just kinda getting sorted on the various things I have to tackle

I need some help identifying more about this motherboard in the machine, I was able to find SOME information on the retroweb “Micronics
80486-25 ISA (v1) (09-00025-xx)”

But honestly I’m looking for potential upgrade path I’d like to get a DX2 installed but I have a fear that this is only a 25mhz CPU supported motherboard.

Additionally there appears to be some trace damage that I am thinking from a leaky battery, is this something I can blast a CR2023 socket on or am I going to have to source some old 5v cordless phone battery and just unceremoniously hot glue it to the case and wing it?

This is endeavor has been exciting and looking forward to all the headaches I’m about to have

Will post pics if this post gets traction or people show interest

Damionsux wrote on 2024-08-15, 18:46:

Hey all, thanks in advance for taking the time to read and reply […]
Show full quote

Hey all, thanks in advance for taking the time to read and reply

I recently came into a few Gateway 2000 computers and just kinda getting sorted on the various things I have to tackle

I need some help identifying more about this motherboard in the machine, I was able to find SOME information on the retroweb “Micronics
80486-25 ISA (v1) (09-00025-xx)”

But honestly I’m looking for potential upgrade path I’d like to get a DX2 installed but I have a fear that this is only a 25mhz CPU supported motherboard.

Additionally there appears to be some trace damage that I am talking from a leaky battery, is this something I can blast a CR2023 socket on or am I going to have to source some old 5v cordless phone battery and just unceremoniously hot glue it to the case and wing it?

This is endeavor has been exciting and looking forward to all the headaches I’m about to have

Will post pics if this post gets traction or people show interest

Your board isn't on the list of those likely to accept an upgrade... https://web.archive.org/web/20010626212953id_ … cs/gw2k_faq.htm

Pics will definitely help re battery damage / replacement

PC Hoarder Patrol wrote on 2024-08-15, 19:50:

Damionsux wrote on 2024-08-15, 18:46:

Hey all, thanks in advance for taking the time to read and reply […]
Show full quote

Hey all, thanks in advance for taking the time to read and reply

I recently came into a few Gateway 2000 computers and just kinda getting sorted on the various things I have to tackle

I need some help identifying more about this motherboard in the machine, I was able to find SOME information on the retroweb “Micronics
80486-25 ISA (v1) (09-00025-xx)”

But honestly I’m looking for potential upgrade path I’d like to get a DX2 installed but I have a fear that this is only a 25mhz CPU supported motherboard.

Additionally there appears to be some trace damage that I am talking from a leaky battery, is this something I can blast a CR2023 socket on or am I going to have to source some old 5v cordless phone battery and just unceremoniously hot glue it to the case and wing it?

This is endeavor has been exciting and looking forward to all the headaches I’m about to have

Will post pics if this post gets traction or people show interest

Your board isn't on the list of those likely to accept an upgrade... https://web.archive.org/web/20010626212953id_ … cs/gw2k_faq.htm

Pics will definitely help re battery damage / replacement

Well dang 🤣 that’s fine I guess about the upgrade https://imgur.com/a/06B975y
Here’s the spot with the damage, I’ve already run some wires to repair those traces

It's kinda hard for a board to be 486SX only because SX came out after DX, though they were only called 486 no suffix then. So default support is DX and they have to spend money beyond the little they have to to make the SX work to make a DX not work. Only situation where you see it is usually by having a soldered down SX and no socket. So got a socket? You can probably put a DX in it, and where you can put a DX you can put a 5V DX2. So there should be a setting though to select between SX and DX and on simple early 486 boards this was invariably a 4 pin header where 2-3 set SX and 1-2 3-4 set DX, so look around for a 4 pin header, W2 sounds likely from the info on retroweb, though it's not depicted on image, since that's a 2-3 setting, if it's only got 3 pins, look close, is there a hole for #4 and it's not populated? Or if it's very clearly only 3 pin, look around for unpopulated 4 pin with a jumper wire on 2-3 or 000 resistor.

I have a Osborne 486 (model LP4D-33C) and i would like to identify this board. I can’t find it from retroweb or anywhere else. I have already replaced the Varta with a Lir2032. HDD Controller gives error on boot. I think traces must have been corroded and im going to try IDE Controller to it. I would also like to install mr.bios to it but can’t find correct bios for 82c495.. there is only 82c495sx in archive.

Anyways.. here is the board.

jnemo2004 wrote on 2024-05-21, 13:36:

About the math coprocessor 3C87-40
Is it correctly mounted in the socket? I believe, it is not.
Thank you

look at pcb - position 387 is marked with white paint. I believe the fpu is placed ok.