DIYbanter - View Single Post - Why aren't computer clocks as accurate as cheap quartz watches?

On 6 Nov 2005 17:55:04 -0800, wrote:

BarryNL wrote:

Maybe 'cos if you really care about accuracy on a PC you can just set it
to update from an NTP server.

Do you honestly believe I'd be interested in accurate oscillators if I
could simply get the time from a network? Much of the equipment is
placed so even WWV isn't available.

OK, so we eliminated the obvious. The typical PC crystal costs $.25 and is
accurate to 20ppm, or 1.7 sec/day, at room temp. It gets worse at other
temps. You can buy a pci clock card with a tempurature compensated crystal
that is accurate to plus or minus 2ppm for $60, and make it your time
server for you network, or if stand alone systems, in each one if it is
that important. Here is one: http://www.beaglesoft.com/clcaspecs.htm

BH