Daylight-saving time kicks in Sunday morning at 2 a.m., three weeks earlier than in the past.

That has some folks concerned the time change will wreak havoc with computer and other electronic systems that automatically update their clocks based on DST.

People may notice their PC clocks or meetings calendars are off by an hour when they show up at work on Monday.

Some VCRs also may need to be reset if they've automatically updated in the past.

Here are some tips to make sure you're on time next time:

Microsoft's Web site (microsoft.com/office/timezone.mspx) can tell you whether you need to worry about your Windows-based PC. If you have the new Vista system, the change will be automatic.

Apple says Mac users should already have received an automatic update to their computers.

Microsoft says those worried about their PC calendars should download a program called tzmove - Time Zone Move - that can update previously scheduled appointments.

Have a BlackBerry? Research in Motion has a patch on its Web site (blackberry.com/select/dst2007/)to fix the problem.If you havea company - issued device, your employer might already have taken care of the DST switch.