Thanks for adding to my haphazard education, Eddy. :slight_smile: I think way back when, there was a time when a clock running slow actually was most likely due to CMOS battery starting to run down, but obviously there’s been lots of changes in system design since then.

I can’t remember ever having a system where the battery didn’t usually outlast the mobo or other critical components. And on every system I can remember owning, the clock has actually run slightly fast, gaining about a minute a month relative to atomic-clock references. (Or maybe the atomic clocks are running slow? :wink: )