system time of a computer

This question might sound stupid to many of you , since I don't know answer for it It thought I would put forth.
When we shut down system or our mobile switchs off, how is the system time maintained? Where is stored that when we restart the computer we don't have to set the time?

Replies

  • Anil Jain
    Anil Jain
    I am not 100% sure, however sometime, somewhere I read that, a battery resides in motherboard which keeps the Time operation active even when the system is not up and running. Make that battery diabled / in-active and the time will stop functioning.

    Any electronics engineer having knowledge about motherboards can enlight this topic in detail.

    -CB
  • Mangesh6688
    Mangesh6688
    The battery which is present on the motherboard is used to store the computer's time and BIOS settings while the computer is turned off.
    This battery supplies power to a chip called the Real Time Clock chip which stores the time.
  • just2rock
    just2rock
    BIOS is what each every cell operation is dependant on the process circulation on motherboard.Now once that is fixed on the board the multivibrator works to ensure clock frequency run at desired frequency as par required for processor like 8Khz,5 khz etc.Now once that is moved out from the board BIOS cant recognizre system runtime process & time syncronization breaks leading to default clocktime as Factory time while the product manufacturing schedule has initially.
  • durga ch
    durga ch
    hmm,
    Brief information i found out with Google research " even when system is turned off, there is a tiny battery on the motherboard which is used to power up the tiny part of memory on the motherboard used for saving BIOS settings. Since the memory is a CMOS memory this battery is also refered as CMOS battery and it's life might last as long as that of motherboard . Hence many of us ( atleats like me) are quite unaware of it.

    more read: #-Link-Snipped-#
    Backup Battery
  • Anil Jain
    Anil Jain
    durga
    hmm,
    Brief information i found out with Google research " even when system is turned off, there is a tiny battery on the motherboard which is used to power up the tiny part of memory on the motherboard used for saving BIOS settings. Since the memory is a CMOS memory this battery is also refered as CMOS battery and it's life might last as long as that of motherboard . Hence many of us ( atleats like me) are quite unaware of it.

    more read: #-Link-Snipped-#
    Backup Battery
    Was just wondering that What about mobile phones?? Do they have CMOS battery as well ??

    -CB
  • Ashraf HZ
    Ashraf HZ
    For computers and laptops, the standard RTC battery is the CR2032 cell.

    For most mobile phones, the actual battery will power the system clock since space is a premium. So once you take it out for more than a few seconds, time and date will reset.
  • durga ch
    durga ch
    rather than taking battery out, what if your battery complelty drains out and you are left with no power? I don't quite remember setting time each time I recharge it back.
  • Anil Jain
    Anil Jain
    I agree with you durga, on this !!!

    Even I never noticed that after plugging out battery, I need to reset the date and time. I saw that sometimes, when I used to change my SIM card.

    -CB
  • Ashraf HZ
    Ashraf HZ
    durga
    rather than taking battery out, what if your battery complelty drains out and you are left with no power? I don't quite remember setting time each time I recharge it back.
    Ah, but how do you define completely drained out? There is a battery cut off level that mobiles have to make sure it has sufficient power to power the time after a period. Below this cut off level, it will refuse to switch on 😀 Powering the time does not require much power.. but it still requires it nonetheless.

    You should try testing the battery with a multimeter when you think its has completely drained out, and you'll see there is still some juice left in it.
  • Saandeep Sreerambatla
    Saandeep Sreerambatla
    In mobile phones there is a option called Auto set !!

    So if you remove your battery /sim card and insert again the time and date will be automatically set to the current time.

    How is this done??

    Everytime I change a place there is a slight update in the time say some seconds, my mobile ask for updation of it.

    From where does it take the time??
  • ONKSSSSS
    ONKSSSSS
    Ha ha you can know your system up time & all other interesting stuff as...

    In RUN panel type CMD & thus open command prompt & type "systeminfo" (without qouts)
  • ONKSSSSS
    ONKSSSSS
    Ha ha you can know your system up time & all other interesting stuff as...

    In RUN panel type CMD & thus open command prompt & type "systeminfo" (without qouts)
    & offcourse hit enter...
  • durga ch
    durga ch
    ONKSSSSS
    Ha ha you can know your system up time & all other interesting stuff as...

    In RUN panel type CMD & thus open command prompt & type "systeminfo" (without qouts)
    & offcourse hit enter...
    Thanks for that, but we are trying to discuss how its done.

    @ ASh,

    You must be right there. May be the power needed to start up the mobile is quite high compared to that need to maintain system time , cool.

    Now left with ES question.
    Are you talking time settings change when you move to different time zone? may be its done on location basis and the time difference from GST.
  • as_nawin
    as_nawin
    i saw all your discussion's
    For system...
    it's nothing miracle on time remains same...
    its a just work of cmos battery in the mother board u can see it beside of BIOS chip thats it..
    if u leave a long gap to switch on the system then automatically the time stops due to battery drain..
    For Mobile....
    There is two technology's u know GSM and CDMA..
    do u know what is diff b/w this....
    in GSM alone u need to set the date and time when u reset the battery...
    but u no need for CDMA..b'coz There is huge tech diff b/w these technology's CDMA has the entire control under the basestation's the date time are given by basestation signal's...
    if u need to know more reply to it..
  • imnitsy
    imnitsy
    as_nawin
    i saw all your discussion's
    For system...
    it's nothing miracle on time remains same...
    its a just work of cmos battery in the mother board u can see it beside of BIOS chip thats it..
    if u leave a long gap to switch on the system then automatically the time stops due to battery drain..
    For Mobile....
    There is two technology's u know GSM and CDMA..
    do u know what is diff b/w this....
    in GSM alone u need to set the date and time when u reset the battery...
    but u no need for CDMA..b'coz There is huge tech diff b/w these technology's CDMA has the entire control under the basestation's the date time are given by basestation signal's...
    if u need to know more reply to it..
    do we have any other technology in mobile..except GSM and CDMA!!!😒
  • Manish Goyal
    Manish Goyal
    There is two technology's u know GSM and CDMA..
    do u know what is diff b/w this....
    in GSM alone u need to set the date and time when u reset the battery...
    but u no need for CDMA..b'coz There is huge tech diff b/w these technology's CDMA has the entire control under the basestation's the date time are given by basestation signal's...
    if u need to know more reply to it..
    hey i have never noticed about this before ..cool..
  • gaurav.bhorkar
    gaurav.bhorkar
    I guess, in mobile phones there is a feature called "Auto update time and date". So, our mobile phone may be synchronizing its time and date with that of the network.
  • rasu3045
    rasu3045
    Hi
    I have faced one problem in my computer.Whenever i power on computer the following error message always come
    Error loading c:/users\suri\Appdata\roaming\aqmdx.dll.

    Anyone help me to rectify the problem.

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