[ntp:questions] ntp-4.2.6p5 on Win 7 x64

Nick me at privacy.net
Tue Jul 22 15:53:52 UTC 2014

> What have I missed?

Having read all the recent posts I have installed 4.2.7p450 binary from 
satsignal.eu to run with -M switch.

Disabled the following drivers;
- delta 44 soundcard
- pe0fko Si570
- com0com

Everything else looks standard; I'm using the on board Intel G31 graphics, 
and the disks use DMA.

The only non-standard services are Adobe Update and NTPD.

The box is very lightly loaded.

ntp runs well on Mint 17 and the drift is reported to be -17ppm.

ntp does not run well on Win 7 x64 and the drift is reported to be +493ppm.

What makes ntpd think that the frequency error on Windows is +493?

wclkres64 reports that performance counter frequency is 2.734MHz.  The QPC 
execution time for 1000 calls varies between 26ns and 37ns.

Given that the PC clock appears to be well within the limits that ntp can 
cope with offsetting NTPD_TICKADJ_PPM will not help.

Other symptoms;

On reboot sometimes ntp starts with leap=11 and precision=-10.  Restarting 
the service does not help.

Sometime ntp starts with leap=11 and precision=-22.  leap:=00 after maybe 
10 minutes.

Using the pool directive plus 3 server entries.  Reach rarely gets to 
377.  Often loses sync and resets.  Ping times to the servers are all 

Any ideas chaps?

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