I have a 286 mainboard here, which is I think very similar to this one here at stason.org. Below is an overview image, and a link to a album with details.
However there are still some discrepancies, so I wonder if someone has an actual manual for this device. I can't find any useful make or model, apart from that it was used by Peacock Computers, but they were just a PC manufacturer in the day, and the T90 label on the upper ISA slot. There are no FCC IDs or anything else identifying the supplier.