[Tfug] PC Clock

[Jim Secan]

At 11:49 AM 11/1/2005 -0700, you wrote:
>But, my understanding is that the OS reads the date & time from the
>battery-powered hardware clock at startup, and then proceeds to tick
>off seconds using a separate, main-powered oscillator.  Thus if you
>leave your system on for a long time the two clocks will diverge. 
>And, when you shut down, the OS might write what it thinks is the
>correct time back to the hardware (my system definitely does this). 
>You didn't go into great detail as to how hard you've looked at your
>problem, so the question is, which is more off, the BIOS or the OS?

This is what my concern was - is this the hardware clock or some other
problem.  I should have said that I mostly run WinXP on this beast, with a
dual-boot into FC3 every now and again (perhaps once or twice a week).  I
don't need hyper-accurate time, +/- a couple of minutes is fine and the
once-per-6h goose from ntp keeps it in line (jitter's not an issue).  I'm
more worried about what other problems this particular behavior is a
symptom of that could bite me.

I don't know if XP runs the clock in software entirely after boot or if it
gets updates from the hardware periodically.  If it's the former, something
is amiss in whatever is clocking the software time-keeping, and that
bothers me a little.  I'm hoping it's the latter, for which a simple
battery replacement might do the trick.

Jim


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