The 486 was extremely dusty. I did not take any pictures when it came in. I bought it because I needed the VLB video card, controller card and audio for another board. After I found this post, I played with the MB for a while, trying out some combinations of RAM, CPU and cards. In the end I put it aside due to its multiplier limitation. It came originally with an Intel 486DX2-66 S (heatsink glued to the CPU) but in the end I used an AMD 80486DX2-80. If found one lying around but, it too, had the heatsink glued. Since AMD does not mark the bottom for these CPU's I pried loose the heatsink but it took some of the top surface with it. With the help of cpu-collection.de I figured it was an AMD A80486DX2-80NV8T.
Here is the motherboard with the original 486DX-2 66-S. I had already removed the 2x8Mb EDO and replaced it with double sided 2x32Mb EDO. Cache shows all banks 32Kx8 20Ns for a total of 256Kb.
Backside of the CPU
Board marking
TK85C418GVIO-4J-D08 for which I found the jumper settings in your documentation! I disabled the HDD/FDC as it was not stable and used a seperate VLB I/O card.
This card ended up on the other 486 board (ZIDA 4DVS, AMD486DX4-100)
The Cirrus Logic GD5422 I used for the benchmarking