Could you get a closer shot of the printed numbers between the 4th and 5th ISA slots? It looks like SN386-8013 but I'm not sure... it could be the model number

What more do you need to know about the chipset? You have the name and the model number. There were dozens of chipset manufacturers in the early 90s, and you just got lucky and found a board with a relatively obscure one.

No info about this model in Internet.
More important for me, to find datasheet or similar motherboard scheme with this chipset. And again, no info about chipset "Solutions" in Internet!

I think I've heard of "solutions" before, but you might have to search on usenet to find references to it.

Why do you need the datasheet? Do you plan to mod the board? For the majority of 386 chipsets out there, the datasheets are simply MIA. Even for some of the well known 386 and 486 chipsets we don't have datasheets yet.

Board is this one. Chipsets are unknown, if you could get it started up, the BIOS string might give a clue. But unfortunately there is one ROM chip missing (this board needs odd/even ROM chips) so getting a replacement would be difficult since the chipsets are unknown, unless you could find someone with the same board.

Edit: xjas had a board with solutions chipsets too, but his BIOS is a single chip. Perhaps can get it from him and split it into odd/even.

Anonymous Coward wrote on 2020-06-23, 02:26:

Why do you need the datasheet? Do you plan to mod the board?

I'm going to fix it. My board is not working now.
All voltages are good, reset at cpu is "low" , 50 MHz quartz generator works well. This frequency came into chip 88c831, but frequency to cpu jump between 20-40 MHz (i havn't oscillograph, so used frequency meter), and it looks like chip 831 trying to start, but goes to reset and repeat.

kalohimal wrote on 2020-06-23, 02:46:

Board is this one.

Very similar, but no exactly my board. Some jumpers located in another places. And on my board exist jumper JP2, that connect D13 pin of cpu to gnd. D13 in 386 datasheet marked as "NA#".

Now i have both original ROM chips. Photo made some earler.

Just because a board has two ROM sockets doesn't necessarily mean it must use both. I have seen boards that can take either a single 512kbit ROM or two 256kbit ROMS in even/odd configuration by setting a jumper.

This board needs both ROM chips. I've merged "low" and "high" bios and can see some readable text in it.

Bios content text strings "AMI Bios 04/15/1990" and "30-0101-ZZ1336-00101111-041591-SYSL". As i understand, manufacturer ID is "ZZ1336".

Unfortunately code 1336 is unknown according to here http://www.idhw.com/textual/guide/inst_mobo_ami_manu.html