Thanks, fellows.

By way of experiment, I wrote a loop that wrote 100,001 GetDate()s to a
table,
with an identity column to record the sequence. That took ~2 sec on
this
server. Then I examined the 100,000 intervals. Their distribution:

Interval (sec) N
0 99855
..13 44
..16 100
..30 1

I conclude that on this particular SQL2000 server, the clock usually
ticks every
160 ms (but not always).

I did this a few times and never saw a negative interval, although
that's not proof
it could never happen.

Thanks again
Jim