larieu
2. I set
hwclock --set --localtime --date="appropriate date" (for example 2008 12 08 10 00 00" )
after that I set
net time set
wait for 5 minutes
the same +40s per minute was seen
That is an indication that the RTC (Real Time Clock).... IC (integrated circuit) is not accurate or maintaining accuracy.
A bios update may resolve the issue, however it's not likely.
You could update the bios and recheck the hwclock again.
Also the OS will not be cause for the RTC to be inaccurate, however there are some software that can correct RTC accuracy, it is dependent
on the hardware (motherboard) supporting that capability.
Typical causes for the RTC not maintaining accuracy are due motherboard RTC oscillators not on frequency or drifting (changing frequency).
There are a few electrical components on the motherboard that support the RTC and are involved with the oscillator frequency control and stability.
Most, not all, motherboards use a 32khz watch crystal to control the RTC oscillator, if the crystal is off frequency then the RTC will not maintain accuracy.
If the Motherboard is in warranty then it is suggested you get it swapped out.
If it is out of warranty you will need to have the crystal changed out should your motherboard have the crystal.
I looked for a picture of that MB, but could not locate one that clearly showed the motherboard to see a crystal.
Also Intel doc's do not indicate sufficient info about the RTC circuit to determine if it has a crystal.
Crystal swap out is a delicate repair, so it's not suggested you undertake the repair unless you have the equipment & skill needed.
The crystal is the small can at the top with the two wires in the picture below, you can see how small it is and some are half that size.
The actual Frequency of the watch crystal is 32.7680kHz and is divided down by the RTC IC to yield a very precise millisecond time base.
If the actual crystal Frequency is 32.7681kHz then the RTC will run a few seconds faster per minute, doesn't take much of a flaw as one can see.
Here's some additional info on the subject
http://www.maxim-ic.com/appnotes.cfm/an_pk/3566These watch crystals
are a standard used in electronic digital and analog watches, TV's, VCR's as well as any electronics that includes a clock and of
course computers, along with the RTC IC.
BTW the only time piece that is more stable and accurate then a crystal controlled RTC is an Atomic Clock, which is used at the sites that computers
sync to in most cases and are also used to maintain accuracy on satellites in particular GPS satellites where accuracy is vital in computing your location
as well as maintaining the satellite location and orbit. Also JFYI..... GPS satellites are in Medium Earth Orbits 12,000 miles from earth, TV satalites are are in geosynchronous orbits 23,000 miles from earth.
Here's the concept with TV satellites, the same 5 watts of power or less (the 5 watt power
limit for CB radios you may use) and the signal travels 23,000 miles to get to your TV "crystal" clear.
That little piece of electronics (crystal) plays an ever increasing part in all our lives by the millisecond every day.
You can track most any satellite including the ISS here
http://www.n2yo.com/ for those who may be interested.
HTH
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