you can set both your sleep & hibernate timings in either Battery mode or AC mode; very straight forward; it is a page in settings where you can a) set up a "power plan" , and on the same page, a setting for 'how long before the unit sleeps", ie-1 sec, 5 sec, 1 minute, 5 min, 15 min, 1 hr, 5 hour, Never (in both battery and AC modes); no matter what I set it at, even "Never" the screen drops off in approx. 3-5 sec (Very aggravating!)....Anybody ??

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