Windows 7: Time changing, date remains correct

At night, when I power down my Vista desktop, the time gets changed to the wrong time, but the date remains correct. Could this still be the CMOS battery?

Thanks

Hello Vincenzo,

It could be either a dead CMOS battery or the time not set correctly in your BIOS settings. In addition, double check to make sure that you have the correct time zone and Daylight Savings set for your location.

Hope this may help,
Shawn

In the BIOS the date was one day behind, the clock a few hours behind. I reset both, then the next day Windows time was off again. BIOS date was still correct, BIOS time was off.
Time zone and DST are correct in Windows, didn't see them in BIOS.

If it was the CMOS battery, wouldn't the date reset itself too?


Thanks

The date will take a 24 hour offset before it would change, so a bad CMOS battery could be the cause.

Time zones don't apply to the BIOS. You need to manually set the time/date there according to your local t/d. Normally, with a dead or failing CMOS battery, the t/d will reset itself to show the time and date when the BIOS software version was installed. Since this isn't happening, it is unlikely to be a bad battery (although you could replace it as a matter of course, they're not expensive).

You could check to see if you are indeed using the correct time zone, as there are several that use the same offset from GMT/UST, but which have local variations (such as dates of operation). In addition, check that you are not 12hrs out, as this is not always obvious especially when using the 12hr system. Finally, consider changing to another time server for your internet time.