Not always. sometimes it can be Vista. This is another possible Vista
bug. For certain systems if you have synchronization checked the
system still can lose time. I had this problem. Switching out the
battery had no effect, system still lost about three minutes a week no
matter what. I confirmed it wasn't the battery by putting it a known
working XP system and that box kept good time with the battery from
the Vista system, so obviously not the battery. That leaves the MB or
Vista.
So time to hunt for a fix in the Registry.
It seems for some there can be an issue with the synchronization
checking phase or the timing circuit is out of phase on some MBs.
Regardless it can be an annoying problem.
By default Vista only checks synchronization weekly. You can alter
this. I set it to check daily. While it still is a few seconds slow,
not as bad by having it sync daily instead of weekly.
The Registry key follows:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\
W32Time\TimeProviders\NtpClient\SpecialPollInte rval\
Be sure to change to decimal value first then change from a value of
604800 to 86400.