OT: Re: Computer loosing time

NoOp glgxg at sbcglobal.net
Thu May 15 23:40:41 UTC 2008

On 05/15/2008 02:22 PM, Rashkae wrote:
> NoOp wrote:
>> Time on the desktops are configured for ntp via pool.ntp.org servers, on
>> the laptop with the dead CMOS it has not been configured and is at it's
>> default (manual). However, I seem to recall that at boot, the laptop
>> does go out to get it's initial time from the Canonical ntp server even
>> if ntp is not installed.
> I think you misunderstand my concern (which, really, has nothing to do
> with Ubuntu, sorry for abusing the list such)

alt.comp.hardware is your best bet.

I think you misunderstand my post - that is; I was responding to
comments regarding the CMOS battery. And pointing out that, even with a
dead CMOS battery _Ubuntu_ will run fine.

> My CMOS clock and battery are both perfectly fine.  It's the system time
> when the computer is on and running that slips.

Really? Have you tried checking the time at shutdown, turning off the
system for a few hours, booting back up, checking system time in bios on
boot to see if the CMOS clock is keeping or losing time? Simply because
you have a clock doesn't mean that the CMOS battery is good. A dying
CMOS battery will cause the system to lose time if it is not supplying
sufficient voltage to the clocking circuits. It is also possible that a
motherboard clocking chip has been set by bios incorrectly, or the
chip/circuit is going bad. Even a bad capacitance device, or bad crystal
can cause the clock frequencies to shift or drift.

> It is my understanding that the OS keeps track of time itself through
> whatever computers use as a timing method now.  I really couldn't care
> less if the time is correct to the second.  My concern is, if the system
> can't even keep track of seconds in an hour, how many other processes
> that rely on timing mechanisms are going to get messed up?

If your OS is relying on _the system clock_, and the clock is losing
time, then it will use and report the time according to the system
clock. If you have Ubuntu set for something other than UTC, it will
periodically go out and get the time from the system clock. You'll see
this option on install; whether to use the system clock or use UTC. Post
the output of:

cat /etc/default/rcS

If it shows:


then it is set to use the system clock.

> Unfortunately, (and you won't see me admit this often) I don't know
> enough about PC hardware to tell you what exactly is responsible for the
> time.. some kind of chip that generates interrupts at a given rate?  Is
> this something specific to the Motherboard or CPU?


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