Ya, it's like anything else, it can wear out over time. that'd be my first guess. try running that mem test too, though I don't know how reliable they are, its worth a shot. Abnormalities in power some times can have an adverse affect on components too. Any brown outs, spikes, or surges in your power lately??? Is your computer on a surge suppressor? You should also try the stick in the other mem slots on the mobo.
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