Well that’s a rarity. It has an Intel 82385 cache controller.

https://archive.org/details/bitsavers_intel80 … onJul87_4494944

Did you check stason.org TULARC?

Thanks for YouR answer. Nop, i didnt chekt there yet. What i know this motherboard is new, i dont know its true or not.

That 96-pin connector is interesting.
Are there any other markings on the back of the board that might show a model number or a motherboard maker?

Nop, its clear from behind

Ps. This motherboard was installed in this case, case Look like new, still with plastic cover on disiplay, little damage on panel, probably by shipping.

That's a nice looking board and a great find overall. Try identifying it on Stason, my guess is that the 96-pin connector is for a proprietary memory upgrade, and those sockets are always drawn on the stason sketches of the boards. Also, for quick identifying, the first and last ISA slot being 8 bit, and only 4 SIMM slots.

I sifted through the pics and didn't see anything quite like it, myself.

Nice!

I have the same connector on one of my boards, see discussion here
Bought these (retro) hardware today

https://www.orosk.com/what-is-pds/

Its Look like PDS from old Apple computers

I am currently searching high and wide for a specific 386 processor board with this very connector.

So far, I only know it to be Nubus connector from older Apple systems... now I know it is also called "Processor Direct Slot"... thank you very much for this.

To the original poster.... that is indeed a nice 386 motherboard, very unusual cache design that I have only seen in one or two other boards. I agree though with another poster that the empty connector is most likely to expand the Dynamic RAM, as there only are 4 slots available which you would really only see on a baby motherboard.... not this full length board, which would require more memory for sure.

Does the board function ok? You have tested?

Yes, the motherboard is working, i ddidnt test it yet, but everything look like new, so i have Good feelings about this MB.

All i know it was bought for replace old workstation in company that i working now, but They never used this, becouse of system transformations in 1989 in Poland.

Das benutzt den gleichen 286er chipset wie dieses: http://retronn.de/imports/hwgal/hw_mainboard_286.html

Ansonsten sind Boards mit dem 80385 nichtr soo selten, hier ist z.B. das CACHE-32A: https://retronn.de/imports/hwgal/hw_mb_chips_386.html

What do you thing guys, is this missing part from my motherboard? Its called Hybrid Memmory Extension

Interesting, seems to match. But I would not dare putting this on my board without knowing 100% its the correct part...

What do you think the connector on my board is for? 😉

Look at the „pass” sticker on MB And extension card, Look the same

I would guess it's one of these proprietary 32-bit expansion slots, before manufacturers standardized on VLB slots. They were often used for proprietary daughter cards, and they one you've posted looks exactly like one. I wouldn't attach importance to the "DIN" format of the slot - manufacturers used whatever was available on the market to create these slots (VLB used a connector borrowed from MCA, PISA slots looked like EISA slots).

The memory expansion fits perfect to my motherboard, sadly it not working. Without ram motherboard can't wake up, its beeping, without ram, but with memory expansion nothing, MB can't boot, with ram and expansion its starting but its freezing during memory count.

????
You dont need that expansion, there is already 4 MB onboard. Was thinking your screenshots of the BIOS above belong to your board?

i find this motherboard:

https://stason.org/TULARC/pc/motherboards/I/I … -386-IT386.html

n0m4d wrote:

i find this motherboard:

https://stason.org/TULARC/pc/motherboards/I/I … -386-IT386.html

nice, try J25 and see what happens