How to I change the CMOS Battery in an old PC? Will I need to flash the BIOS again? Will the computer BOOT after replacing the battery? What type of Battery is needed?
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How to I change the CMOS Battery in an old PC? Will I need to flash the BIOS again? Will the computer BOOT after replacing the battery? What type of Battery is needed?
No flash is required. Just go into your bios and write all settings down so you can reset them after changing the battery.
CMOS/BIOS BATTERY
Excellent help
I'll probably take a lot of flack for this, but when I change a battery, I just hot-swap it (change it with the power on). Bios settings are not an issue then. It does have to be done very carefully though.
Doesn't the computer only draw power from the CMOS battery if the machine is unplugged? If you leave the computer plugged in all the time, it doesn't draw power from the battery then, right?
When your computer is turned off, the battery takes over in order to allow the Bios to remember the Cmos settings. Most motherboards will very slowly recharge the battery when the computer is turned on, but when the computer is turned off, the battery does the work. This is the reason that if you have a dead battery, the computer will "forget" your Cmos settings. This is also the reason you need to write down your Cmos settings when changing the battery, as, when you take out the old battery, the bios chip will "forget" your settings, as the power has been interrupted.
In that case, I can see the benefit of leaving the computer on all time, lol.
With the newer mobo the capacitors will keep things going long enough to change the battery. They store electricity for a while.
Some flack for Leurgy! IMHO the risk of damage to the motherboard or cards is to great to change the battery when the motherboard is live. Recommend you write down the CMOS settings in case you need to re-enter them after changing the battery.