Not sure if this is a good area for a repair thread or not, but if any gurus want to follow along with my attempt at diagnosis/repair then feel free to chime in 😎

Board: STO98-5VL VER: 3.3

https://stason.org/TULARC/pc/motherboards/A/A … AM-33-F-80.html

or?

http://www.elhvb.com/webhq/models/486vlb3/opti495.txt.html

Problem:

Board displays 'Keyboard failure or not present' before post, then drops into bios. Din-5 has some corrosion on the solder joints that I cleaned and reflowed, also corrosion in the port itself. The battery is removed and no trace damage that I can see, looks good, cleaned with toothbrush. The BIOS has corrosion on one side, every pin, not heavy but there. I have not removed the bios chip yet to clean.

I know I need to do more cleaning before moving on. Buuut does the BIOS chip and KBC chip communicate? I'm just scratching the surface in understanding the communication process of these machines. So excuse my ignorance. But its a question that came to my mind while inspecting the corrosion on the pins and thinking that maybe the problem could trace back to bios.

Next step:

Finishing cleaning, attempt another boot, note BIOS version. Record my findings 😎