[CentOS] CentOS 4.5, kernel-2.6.9-55, NTPD trouble

Mon May 21 14:31:44 UTC 2007
Robert <kerplop at sbcglobal.net>

Michael D. Kralka wrote:
> Robert wrote:
>> Following the update this morning, NTP is failing with the same symptoms
>> that I saw several years ago (pre-CentOS, I believe) when Anaconda
>> mistakenly blessed my ASUS A7N8X, Athlon (CPU: AMD Athlon(tm) XP 2600+
>> stepping 00) based system with an SMP kernel.  The symptom is that NTPD
>> never establishes sync with a server, showing over the top jitter values.
> Several years ago with a Gentoo installation I experienced an identical
> problem with an ASUS A7N8X-E Deluxe motherboard, also with an AMD Athlon
> XP 2600+. After a lot of experimenting, I discovered that if the FSB
> Spread Spectrum feature was enabled with ACPI, spurious timer interrupts
> were generated, causing the system (Linux) clock to tick fast and ntpd
> to fail to sync with any time source.
> Who knows whether a BIOS update will fix this problem, but a quick test
> would be to disable the FSB Spread Spectrum feature and see if that
> fixes the problem.
> Cheers,
> Michael
YES!  I changed the FSB Spread Spectrum from "0.50%" to "disabled", 
saved, rebooted and the problem is gone.
Thanks for the help!  BTW, I had already checked for a BIOS update.

Best regards,