Computer clock being set incorrectly

[Enormous]

The past few days I've noticed that my system clock is off by 5-8 minutes every day. Each day I discover this, I sync the clock with either time.nist.gov, or time.windows.com, which returns the clock to the correct time. But after I come home from work the next day, the clock is wrong again. I am running 2.1 RC6, and did not notice this problem prior to updating to the beta. I also have the option to Sync System Clock with SageTV Server set to Enabled. Anyone else having a similar problem? Is it on my end, or Sage's?

Thanks,

[zz5]

When you reboot the computer does the time go back to the correct time?

[Opus4]

Someone was pointing out that the Windows clock can be quite bad. I usually disable SageTV's clock sync, so I have no idea if it could have the wrong time; I just let a utility sync to atomic time quite regularly.

Edit: Oh yeah... that was zz5 pointing that out about the Windows clock.

- Andy

[SHS]

The SageTV Server clock was fix the other day I to start seeing it but not bad.
Full close SageTV reset you time that take of it.

[Enormous]

Thanks to everyone for the replies. I restarted the machine, and the clock is still messed up. But I did take Andy's advice and installed a clock sync utility. Using that, I have been keeping track of how the clock is behaving, and it appears that it is about 20 seconds fast for every hour. So I'm going to have to do some checking to see if there is a remedy for this. My guess is that it is a hardware problem.

[Opus4]

Sort of OT, but I'm so bad about wanting to know what time it is that I broke down and bought an atomic sync utility to carry with me -- a solar powered atomic watch... At least I won't need to reset my watch this weekend!

- Andy

[Enormous]

Yowzers, how *accurate* of you I like it when I don't know what time it is (at least at work), because it's usually later than I think, and close to going-home time!

After researching a bit, I've found lots of people who've had the same problem. The theory I've seen repeated a couple of times is that is may be an nForce2 mobo issue. Not sure about that yet. But I'll post back if/when I find out anything more.

[mls]

I haven't seen a motherboard yet that keeps accurate time in the internal BIOS clock itself. Of course, the Windows clock varies even more. The reason the clocks are not keeping time correctly is due to variations in tolerances of the crystal used for the master oscillator. Windows tends to wander depending how much stuff is running and how many interrupts causing its clock to vary all over the place.

For any real accuracy, one would need an expensive precision cut crystal encased in a precisely temperature controlled oven. Just not practical for a home computer, so the only alternative is to use other software to sync the clock to NIST.

[Enormous]

Well, I put some crystal things in the oven, but I don't think it's helping my clock problems any.

I think I've solved the problem though. I read that on a lot of nForce2 boards, iif you Disabled the FSB Spread Spectrum in BIOS it would stop the system clock from acting up. I did that and rebooted about 2 hours ago, and so far the system clock has been keeping perfect time! So I'll knock on wood and hope it sticks.

[mls]

That spread spectrum stuff varies the clock pulses to various parts of the system. Basically, it's just a cheap shot the motherboard makers are using to get around how boards are tested for the EMI (electro magnetic interference) they produce. Doesn't really do diddly as far as preventing interference to other things, just gets around the testing method used.

For some software it actually causes other problems and system instability. So, yes, turning that off could help solve a number of problems. Hyperthreading is another silly one.

I suspect there are a number of things in the BIOS setup that nobody bothers changing (or even know about) when they build a new computer that may be cause a good share of the problems people are having with SageTV (as well as other things).

Too me a month to figure out the right BIOS settings in the last computer I built so it runs decent. That one had AMI BIOS. I'll never get another motherboard with AMI BIOS again. Just too many hassles.

[mls]

Originally Posted by Enormous

Well, I put some crystal things in the oven, but I don't think it's helping my clock problems any.

Reason I mentioned crystal ovens is because while being an amateur radio operator I had salvaged some army surplus radio transmitters that used them. Also, every TV and Radio station uses a crystal oven to keep their frequency accurate to meet FCC regulations. Those oven often are regulated to less than one tenth degree temp change.

As I said, that's just not practical in a home PC and the crystals used have a wide tolerance spec, so computers do vary a lot in how close they keep time (unless you use extra software to sync to NIST periodically to correct).

[Enormous]

Just an update: Since I made the changes to the BIOS, the clock has been rock solid and has not needed adjustment in over 24 hours. Thanks to all that responded!