Clock randomly resetting?

[rickynumber24]

Not too long ago, my BIOS battery seems to have died, as my system clock wiped a few times on boot. This only happened occasionally, so I didn't fix it originally. I also don't know if it's related to the problem I have now.

Currently, if I leave it booted and wander off for a few hours, when I come back the time is incorrect. It seems to be consistently earlier than it should be (as in it lost a few minutes or hours... generally hours). So far, I only know it happens in Windows, but I will reboot to Linux tonight to see if it happens then, also.

Does anybody have any guesses about what's going on how I might be able to remedy this? Friends I've talked to so far aren't so sure it's a BIOS battery when it's doing this while booted, and I have to agree with them.

[sarbin]

welcome to the forum.

you might want to see if your timezone is set correctly.

[rkawakami]

Welcome to thinkpads.com!

If the loss of time is consistently a random number of minutes as opposed to hours, then I would suspect a problem with the real-time clock (RTC) circuitry on the motherboard. If it's a matter of the system time changing by an hour or two (or more) and it does so only once while booted into Windows, then I would look at the "Internet Time" tab in the "Date and Time Properties" window and see if the "Automatically synchronize with an Internet time server" option is checked.

The RTC is powered by the BIOS (aka, CMOS or backup) battery when the system is disconnected from all other power sources. You could either have a weak BIOS battery, a loose battery connector on the motherboard or an actual problem with the timekeeping circuits on the motherboard. A early T4x system would be about 5 years old; possibly enough time for the BIOS battery to start giving out. About the only thing you can do to verify if it's the battery is to pull it out and measure it with a voltmeter. It should read at least 3.0V. A loose battery connector on the motherboard may be harder to pin down. The RTC circuit can be tested using PC Doctor for DOS, available here:

http://www-307.ibm.com/pc/support/site. ... MIGR-43283 (diskettes)
http://www-307.ibm.com/pc/support/site. ... MIGR-56222 (CD)

The RTC diagnostic is part of the Systemboard section.

[rickynumber24]

Alright, update in the morning...

I left it booted overnight in Ubuntu Linux and I didn't lose a single minute (In fact, I accidentally left it set 3 minutes fast...) so it looks like a Windows-only problem. This could be because of differences in how they handle the clock once things are running, however.

Some information I forgot which might be useful:
- It's a T43p, so it's about three years old.
- The time is changing by what seems to be minutes, because the number of minutes changes also. Additionally, I've seen it lose both more and less time than has passed, with the tendency being to lose more time than has passed when I leave it longer.

Apologies for giving you a scatter-brained first post, but it was late and I was more concerned with getting it posted than making a full report, I suspect.

I'll look into PC Doctor in the meantime, but which screws do I need to take off to get at the BIOS battery? (I've been wondering how to fix that myself for a bit anyway...)[/list]

[rkawakami]

Best resource for information about taking your system apart can be found in the Hardware Maintenance Manual:

http://www-307.ibm.com/pc/support/site. ... MIGR-58791

The backup (BIOS) battery is accessible by removing the keyboard and the keyboard bezel (palmrest). Be sure to keep good track of which screws goes where. The T4x should have a screw length guide on the bottom, with matching numbers at each hole.

With the system being only three years old, I wouldn't think the battery itself is bad. There may be a problem with the RTC on the motherboard.

Before you spend some time opening up the system, I would suggest that you run the RTC diagnostic in PC Doctor for DOS. You can force the test to loop a number of times so that so don't have to sit in front of the system and keep pressing the "execute" button. Here's the procedure:

- boot the system with the PC Doctor for DOS diskettes or CD (CD is much easier if you have a way to burn one)
- when the PC Doctor screen appears, use the trackpoint to click on the "Diagnostics" heading
- that will drop down a list of tests; click on "Systemboard"
- press the F2 key to open up the Test Options window and click on "Set Pass Count"
- enter a large number such as 1000 and press the Enter key
- press the Escape key to close the Test Options window
- click the area in the white column next to the "RTC Clock" line (or use the arrow down key until that line is highlighted, then press the Enter key)

The RTC diagnostic should begin testing. It will loop for as many times as you have specified; 1000 should be about two hours. You might want to try gently flexing the system around. If there is an intermittent connection being broken by moving the system that would be the best way to tell. You can interrupt the diagnostic loop at any time by pressing the Escape key. It might take a few seconds for the test to actually recognize the command so give it some time.

[rickynumber24]

Well... apparently rebooting and complaining about a problem fixed something because things seem back to normal. I think I'll still check the RTC clock sometime, though, just to see if I'm getting lucky.

Thanks for your comments and suggestions! (and, for that matter, motivating me to actually test what was going on more rigorously...)