Electronics do not usually fail during disuse, but mechanicals can, as slomacuser writes. What boot floppy did you use? For a floppy-driven Mac the presence and good condition of a floppy disk at startup is truly vital, if only to ascertain that the FDD still works.

What was the error code under the Sad Mac? What is the condition of the backup battery, meaning has it broken down and gooped onto the logic board? Five years without battery-sparing is a long time, and such batteries are awkward, but not impossible, to get hold of nowadays.

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