On screen clock slows down, why?

[Stallion]

The clock on my wifes PC will sometimes be up to 2 hours behind. Even if we reset it it will be behind (by an hour or more)again within a day. Is it the Mobo? Bios? the PC stays on 24/7.

We have an Abit Be6 II/ katmai550/corsair PC100/ w98

 

[pillage2001]

Chances are the BIOS battery is weak. 😉

 

[Peter]

The "live" clock (while the PC is running) is just an interrupt driven software counter.

If the interrupt load is too high, IRQs will be dropped, and the clock will go slow. This is rare though, in fifteen years of PC engineering I've seen it once - and that was on a 386/20 file server dinosaur running 14 workstations off 7 MBytes of RAM and a single SCSI disk on an ISA controller 🙂

More likely on a modern system is ignorance against sleep modes. The OS, or BIOS, should reload the software driven time from the battery backed RTC when waking up from a powersave mode in which the CPU has been halted. And even if it does, it might still be that the application that displays the time doesn't notice.

Regards, Peter

 

[Stallion]

Thanks for the tips, I'll check it out. 🙂

 

[gtd2000]

I'd simply change the CMOS battery.....very common symptom of it losing power... 🙂

 

[Peter]

CMOS battery is not used while the system is running. Clock going slow while the computer is OFF would be the first indicator of a weak battery (before it loses time and date along with the BIOS settings).

Regards, Peter

 

[gtd2000]

sorry never noticed that the PC was on 24/7...... 🙂
For that sake of about a dollar + or so I'd still change the battery.... 🙂

 

[Big Lar]

My be6-2 does the same thing/ but only loses a few minutes a day/ I did change the battery twice, to no avail, I personally think it's an issue with the abit board.

 

[dennilfloss]

I posted a similar problem with my P3B-F some time ago. My Bios clock keeps track of time perfectly but, as I never put my system to sleep (I crack rc5) in W98, after a few days, the system tray clock starts to lose time and it seems to accelerate until I reboot (when it gets resynched to the Bios clock).