Some time ago i bought some nice dark grey AT desktop cases. (it had to imitate the IBM 286 AT series of computers)

I one of them there was a dusty FIC LEO 386SX - 16/20V motherboard inside.
When powering it up on a test bench it didnt nothing. (no screen or anything (just complete death)
Iam aware off that the dallas battery is flat.
After seeings this on YT from necroware:
https://www.youtube.com/watch?v=sfbqZPLYNpI

The board should just working fine without that empty battery. Yes iam going to remove it later when the board would work.

What i tried so far>

- Removed most of the dust with a black brush from a beard shaver. Did this very slow. To get the upper layer removed.
- I think the board needs parity 30 pin simm ram.. There was already 256K Parity simms on the board. And YT from necroware comfirms it.
- Swapped the memory out for 2x 1MB simms, also set bank 0/1 to 1MB simms.
- I know that this board cant handle 4MB simms, 1MB simms seems to be the max.
- Also lowered the wait states to the slowest, so knowing that the ram inserted shouldnt be a problem. if the wait state isnt to fast.
- Tried different Bios roms..
- Removed the keyboard bios
- First ISA Graphics card wouldnt work great ( some times it worked and sometimes not) Swapped out with a card knowing to work.
- On first sight board doesnt seems to be shorted. ( only dont know if the decoupling tantalum capacitors near the AT power connector are in great shape.)

- Cleaned the first 16 bit slot with a fine grade sandpaper *moved it very slow trough the slot on both sides.
- De oxit D5 -> Keyboard bios socket, Bios sockets, upper 16 bit slot, and two ram slots on bank 0 only (only for testing purepose)

When putting the board on nothing happens.
When i put it sometimes off, i hear a very dim tone from the connected PC speaker.
When directly put it ago one, the board give me some error beep codes.

It seems to be 3 normal ones and 2 fast ones behind.

The bios that its used on the board is from phoenix.
Iam not sure if the bios roms still work or having problems due age.
What i can do is replacing the roms. (but have to order some 27c256 roms)

Can some one tell me what those beeps are trying to tell.
I have already looked with google for these phoenix bios errors codes. But really cant make anything out from it.