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There's a story I read when I was a kid, probably in the 1980-1985 time range, though of course it could have been published any time before that.
Aside from the fact that the protagonist was an Asian-American woman--possibly specifically Vietnamese, though I'm not sure on that point--I only really recall the creepy ending. The woman had had her mind tampered with by an evil machine intelligence that she'd uncovered evidence of earlier in the story. (The story is set in the then present day, so the machine intelligence would have been a novelty.) One by one, several "relays" in her mind close, each compelling her to perform some action. She returns home and disables whatever component that prevents her microwave oven from operating while the door is open. (She was very technically adept and nerdy.) She sits silently for several minutes until the final relay switches off, then puts her head in the microwave and turns it on, to all appearances committing suicide. She may have been sobbing as she did so. It was really pretty disturbing.
And as far as I remember, the story ends there, the machine intelligence presumably going on to conquer the world.
Can anyone identify this story? It sometimes comes to mind when I'm waiting in front of a microwave for something to finish cooking, as it did just prior to my composing this question.