On Thu, 27 Dec 2018 08:42:23 -0200, Shadow wrote:

Sorry Flasherly, I got lost after the first phrase.
I sync to an atomic clock on startup, so it should be within
half a second of "real" time at the end of the day. But I can live
with 30 seconds off.
I was worried it might be hardware failure, but since Linux
does not have the glitch, I'm pretty sure it's just XP having fits
with the amount of CPU and memory at its disposal.

The first written phrase, I provided, corresponds to after your
startup, and that is specific to Dimension 4, in the user settings,
for defining how often Dimension 4 performs an Atomic Clock
synchronization.

The Dimension 4 polling interval, I checked, just after the prior
post, and I've determined that my computer is about 8 seconds faster
than a standalone La Crosse radio receiver atomic clock, on the wall,
behind this monitor.

But the whole point is that if you can go beyond an OS start-up
synchronization event, a more frequent interval timed synchronization
may improve your computer's chronographic accuracy.

OK...checking with the second hand to the Casio. This is my watch:
https://en.wikipedia.org/wiki/File:C...ave_Ceptor.jpg

I'm about 4 seconds fast on the computer, thus my computer is not as
accurate as the Casio. (I've checked the Casio to other standards,
such as a short-wave band radio receiver and England's "Big Ben" timed
broadcast. So my computer is not within 4 seconds near to a
chronograph, nor is Windows or, apparently, Dimension 4.) Checking
the BIOS clock may also be an indicated course to account;- as might
running Linux shed further light on narrowing in on a cause of the
discrepancy for accurate time keeping.

Between a computer crystal-derived signal reference and a WEB software
interface to poll a reference Atomic Clock server, there's no excuse
for this behavior. I believe it would be safe to assume, that you not
build such as a rocket-ship to blast off to the moon, not if you're
designing that trajectory based on a computer's ability to keep timed
accuracy.