If I completely shut down a computer and not use it for months, how can it still tell the time accurately? (given that it isn’t immediately connected to the internet)

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If I completely shut down a computer and not use it for months, how can it still tell the time accurately? (given that it isn’t immediately connected to the internet)

In: Technology

20 Answers

Anonymous 0 Comments

So, a desktop PC has that little battery. What about my phone? If my phone dies and I don’t charge it for 15 hours, how is the time correct when I finally do charge it and fire it up? Same idea? There’s also a little battery in there too?

Anonymous 0 Comments

There is something called a CMOS battery inside the computer on the motherboard. Its basically a very small car remote type battery, you know the flattened CR2032 like ones. Like flattened watch batteries. Anyhow, this battery keeps a timer awake. And it draws very less power to do that. Once this battery is dead, your computer wont be able to tell the time. This battery stays functional even when you switch off your computer.

Anonymous 0 Comments

There’s a small coin sized battery stuck onto the motherboard that powers a clock that keeps track of time.

Anonymous 0 Comments

The motherboard has a small battery about the size of a quarter called a CMOS battery, it’s responsible for keeping time. The MOBO keeps time, and other BIOS/UEFI settings. If the little battery fails, your computer will stop keeping track of those things accurately.

Anonymous 0 Comments

If you have a computer that you turn off and don’t use for months sell it and stick to the comforts of the analog contraptions that your boomer ass has been acustomed to.

Anonymous 0 Comments

There is a small button battery called a CMOS battery. They last for years but not forever. Your average consumer computer is replaced before the battery needs to be. But the do go bad and if the pc off and unplugged it will lose it’s time.

Anonymous 0 Comments

CMOS battery on the motherboard that keeps the data on your BIOS chipset from losing power and resetting to factory defaults. Also there is a time keeping circuit that has a crystal inside it that is designed to oscillate at a specific frequency when specific voltage is applied to it. That is also how the CPU keep its timing as well. Without that crystal oscillator your whole system would be out of whack and nothing would work properly.

Anonymous 0 Comments

Most if not all computers have a 2032 battery on the motherboard that supplies power to keep time and date accurate.

Anonymous 0 Comments

Not all computers do this.

I’ve tinkered with a Raspberry Pi 3, and it absolutely always needed to stay powered on or use an Internet service to know the time.

The difference between computers that can keep the time and ones that can’t is a “realtime clock” (RTC) circuit or chip.

An RTC is typically powered by a little coin cell battery. On a PC, this battery is usually also used to retain some of the computer’s basic hardware settings in its BIOS or UEFI.

Anonymous 0 Comments

There is usually a small “coin” battery on the main board, which powers the computer just enough to keep the date and time. If it were to run out, or you were to take it out, then it would not keep the time.