I pulled this board from an old 286 that wasn't posting. I confirm the AT PSU works as I've tried it with another board. The motherboard model number is KMA-202F-12R and I found a user manual online.

First of all the DS1287 is likely dead but also none of the RAM slots were populated to begin with. I pulled up two random 30pin SIMM modules from my spare parts, put them in BANK 0, set the mobo jumpers for 512k Ram size and SIMM memory selection, but nothing happened. (Disclaimer - I don't really know anything about RAM this old and don't know how to identify modules, their size or compatibility with a given system.) The user manual says the SIMMs should be 256K*9 so I assume this means 9 chips per module. I then tried with other modules with 9 chips each and powered the PSU. I quickly noticed a burned smell and the second SIMM felt really hot so I turned the power off. 😵

I then thought I would try with DIP RAM instead. The user manual says to use "41256" and "44256" chips. I couldn't ID the chips I had in my box of spares but I thought: "what the hell, I'll give it a go... as long as the number of pins match the socket, what could possibly go wrong" 🤣. I populated bank 0 with 6 chips, set the jumpers for DIP RAM and turned the power on. Burned smell was even worse and the chips got super hot.

Questions:

-What happened?
-Did I kill the board?
-Did I kill the RAM?
-Where do I go from here?

I'd love to be able to revive this board as it seems to be a nice one with a 286-12, integrated serial, parallel, floppy and IDE. But I'm afraid troubleshooting it might be beyond my current skills 😖

Here's a picture of the board:

And a picture of my pool of spare chips and memory modules. I got them for free from the same person a while ago when I bought some systems from him, and I've got no idea if they're defective or working.