Solved Clock Drift driving me nuts. Any way to sync to CMOS clock?

[Mugsy]

And old Windows problem has finally reared its ugly head on my system: "clock drift". My Windows clock keeps losing time. About 1 minute by the end of the day.

My CMOS clock is fine and is NOT losing time. I shut my PC off at night, automatically correcting the Windows clock when I restart the next morning. But my scheduled tasks later in the day will start late as the Windows clock slowly loses time.

I've edited the Registry to update "Internet Time" daily instead of weekly, but the time of day that the clock updates fluctuates, sometimes updating in the morning (which is unhelpful.)

"Clock drift" is a problem that has been around since Windows-3.0. As the number of background tasks grows, the software clock has a tendency to lose time.

Since my CMOS clock is just fine and and polling the Internet NTS (Network Time Server) sometimes fails (about 15% of the time), I was wondering if there was a simple way to automatically resync the Windows clock with my CMOS clock?

TIA.

 

[Qdos]

Here's a link to a constantly updated list of NIST servers.

NIST Internet Time Service

If you search for your existing host in Regedit and substitute one from my list for the preset one you should also stumble upon a registry setting to increase the frequency of synchronisation.

It goes without saying you should back up your registry first, as a safety precaution

 

[Lemur]

"

1. Open Date and Time by clicking the Start button
   
   , clicking Control Panel, clicking Clock, Language, and Region, and then clicking Date and Time.
2. Click the Internet Time tab, and then click Change settings.
   
   If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
3. Click Automatically synchronize with an Internet time server, select a time server, and then click OK."

Set the clock


Fix the Windows Clock So It Syncs Properly | PCWorld


Note, I wasn't able to try this as I'm currently on a domain server and didn't want to log off at the moment.

 

[Layback Bear]

Lamur your method has worked for me a long time. I use the time windows.com so my Windows Updates work properly. So I guess I have tested it.

 

[Lemur]

Lamur your method has worked for me a long time. I use the time windows.com so my Windows Updates work properly. So I guess I have tested it.

LAMUR? Heheh. I guess I've been dissed. . Jk...

 

[Layback Bear]

Lamur your method has worked for me a long time. I use the time windows.com so my Windows Updates work properly. So I guess I have tested it.

LAMUR? Heheh. I guess I've been dissed. . Jk...

I mean no disrespect. Only meant to say your suggestion works for me.

 

[Mugsy]

Thanks to all who replied, but clearly no one bothered to read my entire post.

Changing my NIST server won't solve the problem as I can't ensure the time of day that my clock is updated.

I already use a different server (time.nist.gov) to reduce the chance of failure when it checks, but I don't want to be dependent upon my Internet Connection to set my clock. My CMOS clock isn't losing time, so I want to simply sync the Windows clock with my internal clock. I can do that 10 times a day if I wanted (I don't).

The biggest problem using an NIST (as I already mentioned) is I can't ensure WHEN it updates (sometimes in the morning... when my time is already correct, or late in the evening AFTER most of my Scheduled Tasked have already been called.)

I need a shortcut or script to sync my clock that doesn't rely on making a connection to NIST and I can run from a Scheduled Task.

 

[logicearth]

Trying to sync the windows clock to the CMOS Real-time clock is pointless...Its already using it! Its Windows itself that keeps it in sync. Also, losing one minutes is hardly anything when most clocks in the world lose more then that daily.

 

[Mugsy]

Trying to sync the windows clock to the CMOS Real-time clock is pointless...Its already using it! Its Windows itself that keeps it in sync. Also, losing one minutes is hardly anything when most clocks in the world lose more then that daily.

Sorry, but neither statement is correct.

Windows does not read the CMOS clock every second to display the time. It reads it once at startup and then uses a "software" clock routine built into Windows to keep time. Background apps have a tendency to "distract" Windows just enough so the software clock loses time as the day progresses.

Windows resets the clock using "Network Time Servers" which use Atomic Clocks that lose about 1 second every 1,200 years. Internet clocks do not naturally lose time.

I schedule recordings that need to start at EXACTLY the same time every day. I don't want them starting a minute late or ending a minute early.

 

[Qdos]

If you did what I suggested in the registry you could have Windows automatically correct its clock whenever it falls more than 'n' seconds out of sync' with the time server selected.

Your CMOS clock has nothing to do with it, as pointed out by others...

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Config
Version

This entry controls the period of time for which spike detection is disabled in order to bring the local clock into synchronization quickly. A spike is a time sample indicating that time is off a number of seconds, and is usually received after good time samples have been returned consistently. The default value on domain members is 5. The default value on stand-alone clients and servers is 5.

http://technet.microsoft.com/en-us/library/cc773263(v=ws.10).aspx

 

[Lemur]

I know you don't want Internet time, but ...

Here are some programs. I know at least one you can specify the # of times it updates the time per day.

Free Time Synchronization Freeware downloads and reviews from SnapFiles

 

[Mugsy]

If you did what I suggested in the registry you could have Windows automatically correct its clock whenever it falls more than 'n' seconds out of sync' with the time server selected.

Your CMOS clock has nothing to do with it, as pointed out by others...

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Config
Version

Thanks, I'll try that. Your reply was overlooked as it was mixed in with everyone telling me to use a different server. I'm not clear on how Windows can tell it is out of sync w/o actually polling a time server or the CMOS clock, but I don't need to understand "how" something works as long as it does.

I'm a little concerned about changing my "interval" from the default setting of "900" down to just "5". How frequent is that? Every 5 milliseconds it will be checking my clock?

 

[Qdos]

I would seriously *not* poll the server more frequently than twice hourly as doing so more often could in itself cause errors in the Windows clock.

If you Google the registry key I've highlighted there are numerous web-pages surrounding the issue.

 

[Mugsy]

I would seriously *not* poll the server more frequently than twice hourly as doing so more often could in itself cause errors in the Windows clock.

Yes, that's part of the reason I asked to sync to my CMOS clock instead.

 

[Mugsy]

Looks like that worked.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Config
Version

This entry controls the period of time for which spike detection is disabled

Just a follow-up. After four days since making the noted Registry change, the problem appears to have been resolved. Yours was the only mention of "spike detection" I've read from anyone on this issue. MS should issue a patch.

Thanks.

 

[idsanity]

I don't know why people had such a hard time understanding your question. While I don't know how to resync with your CMOS clock, I have found this to be the most reliable method of keeping time accurate: Make Windows synchronize time more often

 

[Mugsy]

Thanks for the reply to my old post, though I eventually found a fix after a bit of searching (I've long forgotten what it was), but I know it included polling the Time Server more often... which is a bit of a no-no, and eventually, even that wasn't enough.

I don't remember the exact cause, but it had to do with certain tasks using up too much CPU time too often, along with too many Tray apps (no more than ten, but that was enough to bog XP) causing the RTC to lose time.

I've since moved to 64bit Win7 and no longer have the problem. Thx.