[ntp:questions] 10 identical PCs, but different clock drifts.

Unruh unruh-spam at physics.ubc.ca
Tue Mar 3 00:02:01 UTC 2009

ryad.bek at gmail.com writes:

>Hi everybody,

>I've bought 10 PCs with identical hardware (motherboard,...).
>The PCs are located in the same room and running identical
>configurations for 4 days now.
>They are synchronized using garmin 18 GPSes.

>I've just checked the NTP's loopstats file and it seems that all drift
>are different.
>Here are the reported drifts (4th column of loopstats file) :

Of course. The quartz crystals which run the on board clocks differ
slightly. Remember that PPM is parts per million. YOu are seeing that the
crystals differ by parts per 100000 which is pretty tiny. They are cheap.
They are not exactly the same. This is like if you weighed the computers
and complained that their weight differed by milligrams. Yes, it does. 


>As all hardware are the same and brand new, I was wondering if you
>find that normal or if there is a problem with my HW config?

Completely normal. 


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