[ntp:questions] 500ppm - is it too small?

[David Woolley]

Unruh wrote:

> 
> I could define hardware outside of 1PPM as broken. the whole purpose of 
> ntp is to take broken hardware and make it deliver the time accurately.
> After using ntp, the computer will NOT deliver time that gains or looses more than 43 sec per day.
> 

A reasonable expectation of a cheap crystal is 50ppm static plus <10ppm 
temperature dependent.  When one gets >500ppm it suggests the problem is 
rather worse than poor crystal tolerancing.