text: a question about clock on xp.? some one please answer me that my pc clock always changes automatically but i adjust it again but after 2 or 3 days has the same situations.  i work only with my pc and have a password. theres a 3v cell on your motherboard. just like the ones that you can find on digital diaries. i think the cell is weak and you need to replace it. the time keeps changing due to the weak cell. happened to me. i changed it and my clock is working fine.   oh and removing the cell will reset your bios, time, passwords etc. so make sure you set your time in the bios by pressing del after you switch on your computer.