Most often, the time is reset after turning off the power, if the battery fell on the motherboard, but this is not the only possible option, and I will try to tell about all that I know.
If the time and date are discarded due to the seed battery
Motherboards of computers and laptops are equipped with a battery that is responsible for saving the BIOS settings, as well as behind the clock, even when the PC is turned off from the outlet. Over time, it can sit, especially it is likely if the computer is not connected to the power during long periods of time.
It is the described situation and is the most likely the reason that the time is shot down. What to do in this case? It is enough to replace the battery. To do this, you will need:
- Open the computer block and remove the old battery (do it all on the PC turned off). As a rule, it is held by the latch: just press it on it, and the battery itself will "pop up."
- Install a new battery and collect your computer back, making sure that everything is connected as it should. (Recommendation on the battery read below)
- Enable your computer and go to the BIOS, set the time and date (recommended immediately after changing the battery, but optionally).
Usually these steps are enough so that time is no longer reset. As for the battery itself, it is almost everywhere that 3-volt, CR2032, which are sold almost in any store, where there is such a type of product. At the same time, they are often presented in two versions: cheap, rubles for 20 and expensive for a hundred more, lithium. I recommend to take the second.
If the battery replacement did not help correct the problem
If even after replacing the battery, the time continues to be born, as before, then, obviously, the problem is not in it. Here are some additional possible reasons resulting in resetting BIOS, time and date settings:
- Defects of the motherboard, which could appear with the time of operation (or, if this new computer was originally) - here it will help contact the service or replacement of the motherboard. For a new computer - an appeal under warranty.
- Static discharges - dust and moving parts (coolers), faulty components can lead to the appearance of static discharges, which can also cause CMOS reset (BIOS memory).
- In some cases, an update of the BIOS motherboard is helped, even if the new version has not come out, can help repeat the old one. Immediately I warn you: if you update the BIOS, remember that this procedure is potentially dangerous and do it only if you know exactly exactly how to do it.
- A CMOS reset can also help with jumpers on the motherboard (as a rule, it is located next to the battery, has a signature associated with the words CMOS, Clear or Reset). And the reason for the discarding time may be a jumper left in the "Reset" position.
Perhaps these are all the ways and the reasons that I know for the specified computer problem. If you know additional, I will be glad to comment.