What the..?!

This problem has been happening ever since I got off the train coming from college. I have a HP Pavilion dv6000 with Windows Vista Home Premium. I don't know when it happens but my clock is usually wrong as if it stops working for an x period of time. For example at 11:19 this morning it said 4pm, the day I got home from college it did the same thing.

My guess is the CMOS battery got loose on the train, since I was using it there but I don't want to go opening my laptop (I'm apprehensive about that since I've never done it before) for no reason. Also I would assume the CMOS battery getting loose would produce other problems.

Btw, the laptop is only a month old at most.

Was this a high-speed train, travelling at, say, half the speed of light? If so, was there a cowboy watching the train speed by? Did, right when the cowboy was watching the train speed by, lightning strike the front and the back of the train? If so, your computer's clock may have gone back in time a bit - depending on who you ask...

Either that, or it's the CMOS battery!

why don't you try contacting the HP support for that.

however the problem might occur if something is wrong with the automatic time updating (but that i think works only if you travel long distances).

Clocks should typically be accurate to within a few seconds per day. If you're experiencing massive clock drift on the order of minutes per day the first thing to check is your source of power. On some computers time is calcualted by the real-time clock chip using the Hz of the input line voltage.

Of course, if it's been unplugged during traveling, it could have been simply a case of low system battery power. If your system battery (not CMOS) is running low or faulty, it could cause the clock to run slowly as well. (Most laptops I have worked on use the system battery for time rather than the CMOS...CMOS is for holding volitale system configuration info in the BIOS only.)

One thing you can try is to go into the System Properties and under the Remote tab, uncheck the "Allow Remote Assistance connections to this computer" box. This apparently frees up a port to allow the computer to sync with the time server. I know it sounds crazy, but it worked on a Dell that I have here in the shop.

Another thing to try is to change the ADM settings in your BIOS. The BIOS advanced power management (ADM) function can cause incorrect time readings on the PC clock. Try disabling the BIOS Advanced Power Management function. Also, the Windows Advanced Configuration Power Interface (ACPI) specifies when components should be active or inactive to conserve battery power. Conflicts between time values in the BIOS and Windows setting can cause irregular computer clock operation. Make sure the current power scheme is set to "Portable/Laptop".

You can try a simple workaround if that doesn't fix it...so long as you have a readily available internet connection:

Open the registry editor and find these keys:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\NtpClient
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet002\Services\W32Time\TimeProviders\NtpClient
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet003\Services\W32Time\TimeProviders\NtpClient

Modify these 3 registry keys by changing the value to 3600 decimal. (forcing the Internet Time Service to update once per hour instead of the default, which is 3 or 5 days, I don't remember which.)

You'll have to specify a new internet time server, as the Microsoft server will not allow updates that frequently. I'd use one of the NIST time servers.

On a related note...it seems that there have been reports of some audio drivers causing problems with time on some dual-core desktops and notebooks.

I have not personally seen this, and I have no idea how accurate this is, but from what I have been told, when a sound is played, such as the Windows default "beep", the RTC loses 20 seconds or so.

Appears that there is a bug in the drivers code that modifies the wrong register. Don't know what brand audio card this was, but I'd look into updating my drivers and what not, just to be sure.

Hope this helped.

I'm with Neg; your laptop now pre-dates the Internet. :D

Windows gets it time from the BIOS by default, if the Windows time is wrong and you haven't installed a third party app (Atomic clock etc) and the region / time zone is set correctly then there is almost certainly a BIOS fault - have you checked that the BIOS date and time are correct?

You can force Windows to use an Internet time source by editing the registry as mentioned in the post above but this does not fix the actual cause of the time issue.

If it is only a month old I would very much consider taking it back to where you got it and let them investigate if from a hardware PoV.

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Originally Posted by Nokia

Windows gets it time from the BIOS by default

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DOH!!! As usual I overlook the obvious...ROFL!

Well, now it's forgetting my power settings from time to time. And it was a long train ride, 12 hours long. High speeds yes, however the cowboy was kinda busy trying to get back on his horse and lightning did strike very close to the train (all true except the cowboy) but no time travel. :(

I'm very iffy about contacting HP because if they ask me to ship my laptop that might be a problem since I'm going back to college in 2 weeks and I need my laptop...

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On some computers time is calcualted by the real-time clock chip using the Hz of the input line voltage.

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Hell when did this start happening? or more importantly WHERE did you get this information? ..probably the same place that tell people that reversing the connection on their televisions will transmitt pictures to the waiting world..
Far out.. The mains frequency can vary upto 10%.. that will result in an error of seconds per hour not month ..

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Of course, if it's been unplugged during traveling, it could have been simply a case of low system battery power. If your system battery (not CMOS) is running low or faulty, it could cause the clock to run slowly as well. (Most laptops I have worked on use the system battery for time rather than the CMOS...CMOS is for holding volitale system configuration info in the BIOS only.)

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Well most of this is BS.. the same battery that keeps the CMOS setting up also powers the RTC Chip (This little chip also has a Quartz xtal to help keep the beat in time..)

Mucking around in the registry is only for time service/update issues.. and that helps to keep the minute per month errors sorted

As for the time shift problem.. you already have most of the answer.. certainly start with the CMOS battery.. suspect a Mobo issue.. if the CMOS battery is OK.. now here is how to tell if it could be a problem..
is it over 3months old? if yes then you have a better than 75% chance of it being the culprit.

It isnt rocket science checking the CMOS backup battery.. but you will need a DVM (Digital Volt Meter) and know that any reading below 3V is not good and any reading above 3.6v is worse or your not metering the battery

Hi Raion,

If you are reluctant to open the box (understandable as it is still under warranty) you might like to start with a simple test?

1. Power up your machine (from the mains) set the time and date very carefully, and run it for a few hours.................by that I mean leave it powered up, I don't think it matters if you are actually doing anything....then check the time.

Do not allow it to connect to the internet: we don't want it to "phone home".

2. Power down and unplug it from the mains. Leave it a few hours and check the time.

If #1 keeps the time and #2 does not then it means that the "clock" is working and your CMOS battery is not.

It is just possible that neither will work. This would be a chip/MoBo error or HP have taken a timewarp backwards in their design :eek:. I only have one machine that would possibly show those symptoms with weak CMOS batteries......... and that is an Amstrad that must be at least 15 years old (it has 4 AAs in a compartment beneath the monitor............ no batteries = no boot).

Please remember that a button cell is usually a cheap, disposable component that is liable to fail at any time. In this case I suspect that the battery may have worked loose and is no longer making contact. In that situation it will meter as "good".

That could be a problem in its own right, as laptops are supposed to be portable. If it is the case, hopefully it is because the battery wasn't inserted properly when it was assembled, otherwise the battery holder is defective.

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On some computers time is calcualted by the real-time clock chip using the Hz of the input line voltage.

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I can see that working with early electric clocks, but IIRC they needed a power supply conditioner to make sure that they got a "clean supply". That technology must be at least 40 years old?

The CMOS RTC runs off DC (3.3v?) so it does not read the raw AC input.

I believe that you are right about HP wanting the machine returned. I would check to see if you have an authorised repair agent close to you.

:)

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Originally Posted by Und3ertak3r

Hell when did this start happening? or more importantly WHERE did you get this information? ..probably the same place that tell people that reversing the connection on their televisions will transmitt pictures to the waiting world..

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Plug your Laptop into a generator and watch the time drift (of course this could have been due to me having a piece of crap laptop)

I know for a fact that at least one brand of laptop (which will remain nameless ...but i will say that they are made in South Africa and private labled to some of the larger comp mfgs/distros) uses input AC voltage to drive the clock. Talk about cheap.

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Originally Posted by Und3ertak3r

Well most of this is BS.. the same battery that keeps the CMOS setting up also powers the RTC Chip (This little chip also has a Quartz xtal to help keep the beat in time..)

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Most modern RTC IC's have a battery integrated into the IC. If affore mentioned battery is defective, it will resort to Main battery. Remeber that there are also 2 clocks on the machine...a hardware one (the RTC) and a software one called a timer-counter that runs independently of the Hardware clock. The timer-counter uses the CMOS battery, not the RTC chip.

The hardware clock (RTC) is based on the Motorola 146818 Real Time Clock Chip, or a functionally equivalent device. The software clock (timer-counter) is usually a device equivalent to an Intel 8254 timer-counter.

When the computer is turned off, it runs on batteries (CMOS battery for the Timer-Counter, and an integrated battery for the RTC). When the computer is turned back on, the software clock starts running again and sets itself (usually within 1 second) to the hardware clock. Although the two clocks are synchronized at start-up, they may run at very different rates and will probably gain or lose time relative to each other while the computer is running.

The hardware clock is updated once per second and cannot display fractions of a second. For this reason, it cannot be read or set within better than a second. The accuracy of the hardware clock is determined by the quality of its time base oscillator (typically a 32.768 kHz crystal). Most offer only marginal time keeping performance. They are sensitive to temperature and other factors and are often not calibrated at the factory. Even under the best conditions, these oscillators are not likely to be stable to better than 1 part per million (about 0.1 seconds per day). In actual operation, most hardware clocks seem to gain or lose time at a rate of about 1 to 15 seconds per day, with 5 or 6 seconds per day being "typical".

In contrast, in order to calculate time the timer-counter will typically generate an interrupt every 54.936 milliseconds, or about 18.206 times per second. Another routine counts the interrupt requests and generates a time-of-day clock that can be read or set by other software programs. For example, Windows uses the information from the software clock when it date-and-time stamps files. Its accuracy is limited by the stability of the interrupt requests. Any change in the interrupt request rate causes the clock to gain or lose time. If you leave your computer turned on for long periods, the software clock might be off by large amounts--perhaps a minute or more for every day that the computer was left turned on.

It's also possible for an ill-behaved software program to use the timer-counter for another purpose and change its interrupt rate. This could cause the clock to rapidly gain or lose time. Another problem with the software clock is that it cannot display all possible time-of-day values. The resolution of the clock is limited to the interval between interrupts, or about 55 milliseconds as stated earlier. Only times that are even multiples of this interval can be displayed. For example, 00:00:01.00 could never be displayed by the software clock. The closest possible values it can display are 00:00:00.98 and 00:00:01.04.

IF the problem is the timer-counter (software) clock drifting while the power is running...replacing the CMOS battery would not fix that. When the system boots, the timer-counter sets to the time of the RTC. So it would appear that the root problem is the RTC, and replacing the CMOS battery won't do squat to fix that IF the RTC runs on an integrated battery on the IC. At boot, the two clocks will sync and the software clock will set to the erroneus time given it by the RTC. If, however, it's a RTC that shares the CMOS battery with the timer-counter (which is certainly possible), then yes, a CMOS battery replacement WOULD fix it. There are a plethora of reasons for a clock to run slow while the laptop is running...but if it drifts when it's off there are only a few.

By all means replace the CMOS battery, I wasn't trying to say that this shouldn't be tried. The laptop ones a re a little bit more expensive than the standard 3v 2032's used on desktops, but it's by far the cheapest thing to try.

Another thought...has he checked to see what the BIOS time is? Also, did his laptop need a BIOS update to handle the new DST change?

As he has said that the system forgets his power settings, I'm thinking that it's the Windows ACPI. As I said earlier the ACPI specifies when components should be active or inactive to conserve battery power. Conflicts between time values in the BIOS and Windows setting can cause irregular computer clock operation. This is a known bug on several HP notebooks (although not sure if your particular model is one of these).

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Originally Posted by Und3ertak3r

Well most of this is BS..

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I never said it wasn't...I'm surely not an expert by any stretch :p

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Originally Posted by Und3ertak3r

Hell when did this start happening?

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Probably about the same time I got abducted by aliens :S


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--EDIT: After looking at the system maintenance and service guide for your laptop it is very clear that your RTC does indeed have its own battery seperate from the CMOS battery...however it is an external replaceable battery, HP part number 431436-001. Cheapest one I can find is about $23.00 USD. (http://www.jpcparts.com/page/search2...ber=431436-001)

It appears to be replaceable without complete disassembly of the laptop- remove the memory expansion door on the bottom of the laptop and any DIMM(s) in there and you'll see it...just unplug the little dongle coming from it from the system board and it should come right out - too easy.

Download this file for future reference - HP Pavilion dv6000 notebook Maintenance and Service Guide (http://h10032.www1.hp.com/ctg/Manual/c01035677.pdf)

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