Every time I open my computer, time and date are wrongly set so I still need to reset it. Any help or site?

Can you anyone help me solve my problem so that when I open my computer it will record the exact date and time? Thanks in advance!|||dead battery on the mobo. if its a desktop, open the case and it's fitted on the mobo.if a laptop they are usually accessible check the manufacturers web site for access/replacement.|||If its a completely different time and day every time you reboot or turn it off then your bios battery is dead. Its a small battery the size of a dime instead your computer. Depending on your computer you would need to find it and get a new one.