What does the error say exactly?, try to use some custom firmware which allows you to disable fan check all togther to ensure that it is'nt a fan-related issue, althought if this error only shows when you plug in the bad hashboard -- it's more likely to be a hashboard related error.
It's almost impossible to find the issue just by looking with your bare eyes, but try to look for solder balls built up around the chips, you might use a phone camera to zoom in.
In order to post the logs you need to use the code tag
If the forum doesn't allow you to post that many chars, use something like https://justpasteit.in/ and paste the link here.