Deunan wrote on 2020-04-29, 23:56:

Yeah, that mobo is really an early AT clone, before most of these chips got integrated into ASICs. But that also makes the repair possible. If a mobo has a faulty ASIC you're out of luck but these chips can be still bought .

Very true ! Assuming the actual board does not have some micro cracks in any of the traces and inner planes then it should be repairable by just replacing some bad parts if those bad parts can be isolated. Once worked on an old XT that was built similar and after many many months of new chips, caps, transistors, etc spent near 2X on parts over buying one that already tested as working just because I want to fix that old board. Then I stumbled on one nearly identical that worked fine and ditched that old one. As long as good functioning XT and 286 boards can be found for $100 or less then all that extra work is not worth it unless it is a very special rare board imho.

Horun wrote on 2020-04-30, 02:12:

As long as good functioning XT and 286 boards can be found for $100 or less then all that extra work is not worth it unless it is a very special rare board imho.

Ha, good for you, but not everybody lives in the USA. There were very few early PCs in Europe and almost none behind the iron curtain, good luck finding one now that's cheap and still works. Importing stuff from overseas is also not cheap and often USA-based sellers ask some silly shipping prices that start at 50$ or more for a single extension card.

Plus, repair is part of the fun. If it gets difficult and frustrating then just switch to some other projects for a time. Weeks to months sometimes pass when I do that and often I come back with some new ideas to try.

Deunan wrote on 2020-04-30, 08:53:

Plus, repair is part of the fun. If it gets difficult and frustrating then just switch to some other projects for a time. Weeks to months sometimes pass when I do that and often I come back with some new ideas to try.

I agree but there is (for me) a point where I will quit trying to fix one, specially if I see no progress. That board I mentioned never booted at all when I first got. After months of work trying to at least get something out of it, Never got beeps or any screen of any kind. Do have some 1/2 repaired with a KB error on one and a Parity error on one other, that were dead to start. Those boards will be gone over again soon but that damn old standard XT board just could never get anything from it. My grandad used to say something about "flogging a dead horse", think he meant that there is a point where it better to give up on something then continue if (as I said) there is no progress.