>I don't know what units TIMER_FREQ is in.  Taking a naive guess, I add 512
>to it, giving me 1189712.  Since you suggest overcompensating, perhaps
>1189800?  

The units are in hertz ... it's the frequency for some PC-compatible
interval timer which is used at the clock interrupt (it doesn't
interrupt that often ... I believe there's a counter so it's some
multiple of that, but it's been a while since I've looked at it).

512 PPM of 1189712 is 609.  You could start from there (add something
approximately close to that).  I don't recall if 512 is the maximum PPM
reported by ntpd; I don't remember seeing anything higher.

--Ken