The time always seems fairly accurate but ntptime reports the frequency correction anywhere between -220 and 200 ppm. My PC is usually on about 6 hours a night and during that time the frequency seems to diverge from zero in either the positive or negative direction but always the same direction between restart/reboot. I have tried changing the drift file after stopping ntpd in PCC then restarting ntpd, restarting pc, rebooting pc. Verbose startup and shutdown report the hardware clock is synced to system time at shutdown. In minime 2009 frequency correction was consistently between 20 and 40. I'm using the same set of time servers I've used for 2-3 yrs.
phenom II x4 945
4g kingston hyperx ddr3 1333
msi geforce9500gt 1gddr2
thermaltake case with led fan that is way too bright
more detail if interested/needed/wanted...