I open this discussion because very often we have in our hands motherboards that cannot be repaired, or it is not convenient to do so, so I thought, why throw everything away, when in reality there may be chips or other things that we can reuse, not necessarily on other MB, but they could be used on the PCB of ISA cards, there are several models, for VGA LAN Audio Controller cards etc...
So maybe you could suggest, what chips can be recovered from a MB, for example could the I/O chip be reused in an FDD IDE controller ISA board? I guess so, unfortunately I am not an electronics technician, and despite being quite ignorant on the subject, I have an idea, but I need your help, and your suggestions, for example, I am working on an XT ISA 8 bit PC , and I don't have an FDD controller, I wanted to buy one, but they can't be found and they cost a lot, while buying a PCB is quite convenient, buying all the necessary components is not easy, and maybe not even cheap, so if I can recover pieces ( chips and more) from a scrap MB, or from scrap boards, I could make a self-built board, without spending a fortune.