I have a PC that will not keep the correct time. One day it will be fine and then in a couple of days it will be fast. Windows still says the correct time, it just the bios. I have replaced the CMOS battery and its still doing it. Does anyone have any clue on whats going on? Could this be an issue with that stupid little pulse crystal? any help would be great thanks
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BIOS ?
- Thread starter clmowers
- Start date
electronicsfreak
Technical User
Run this scan for there is a virus that changes time. Not sure if you have it or not but a scan is worth checking out. Heres the link for an online scanner.
clmowers,
Windows gets it time from the System clock(BIOS) and does not have it's own time base. Unless you have windows connecting to an atomic clock site for update, it reads the system clock.
I have to echo electronicsfreak's suspicion of an outside culprit.
rvnguy
"I know everything..I just can't remember it all
Windows gets it time from the System clock(BIOS) and does not have it's own time base. Unless you have windows connecting to an atomic clock site for update, it reads the system clock.
I have to echo electronicsfreak's suspicion of an outside culprit.
rvnguy
"I know everything..I just can't remember it all
I think that the OS reads the real-time clock once at power-on, then it uses the system timer tick (55mS) as its time base for the clock activities. This timer tick coming from the base CPU clock oscillator which is stable but not necessary at an exact center frequency, a system that is never turned off may drift slowly, compared to the internal real-time clock. Unless XP has corrected that?
clmowers, there's usually an independent crystal for the real-time clock. Some mobos also have a sort of clock module that includes everything.
Dust may be enough to disturb a crystal. Can you clean the area where you see crystals?
clmowers, there's usually an independent crystal for the real-time clock. Some mobos also have a sort of clock module that includes everything.
Dust may be enough to disturb a crystal. Can you clean the area where you see crystals?
- Thread starter
- #6
The pc is a dell optiplex gx280 with the a09 bios. XP Pro sp2 with all updates. Just a very basic PC
Well I did open the pc their was some dust so I cleaned that out. I ran the Virus scan and It found nothing.
The PC is on 24/7 as I am using it as a server for my alarm system. I have my clock set by AD on the DC. Which I think, if I remember right, it is getting its time from good old microsoft.
Felixc - What would cause the time to drift off? I have 13 other server and non of them do that.
Well I did open the pc their was some dust so I cleaned that out. I ran the Virus scan and It found nothing.
The PC is on 24/7 as I am using it as a server for my alarm system. I have my clock set by AD on the DC. Which I think, if I remember right, it is getting its time from good old microsoft.
Felixc - What would cause the time to drift off? I have 13 other server and non of them do that.
If the drift is not constant it is puzzling. I have seen it on my motherboards with RTCs that had a marginal crystal, about one unit out of 200. Changing the crystal solved the problem, but I doubt that you have anything to do such a repair. The drift was varying with the temperature, sometimes making the RTC count too quickly or too slowly. Does your RTC keep the time at all when the power is off?
Is this your only PC that is used as a server for your alarm system?
Is this your only PC that is used as a server for your alarm system?
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