During a routing cleaning of the inside and outside of a desktop computer, you notice that a small battery is mounted on the motherboard. What is this battery used for?
A) It keeps the system memory intact when the system is in “hibernate” mode
B) It powers the internal system cooling fans
C) It’s an on-board uninterruptable power supply (UPS)
D) It maintains the state of the BIOS settings
The answer: D) It maintains the state of the BIOS settings
Although most BIOS startup code is stored in non-volatile flash memory, your system’s individual BIOS settings are stored in dynamic RAM that requires a constant power source to keep the memory intact. Without the constant system power or backup power from the battery, your BIOS settings would be erased each time you unplugged your system from the power source.
The incorrect answers:
A) It keeps the system memory intact when the system is in “hibernate” mode
The hibernate mode of a computer writes the contents of memory to disk and powers completely off. There’s no additional power required to sustain a hibernate mode.
B) It powers the internal system cooling fans
It takes more than a single “button” battery to power most cooling fans. If you track the power source of the cooling fans back to their source, you’ll find that they connect directly to the computer’s large power supply.
C) It’s an on-board uninterruptable power supply (UPS)
Wouldn’t that be nice? Unfortunately, it would take much more power than a small watch battery to keep an entire computer up and running. There are large UPS systems available that sit outside of a desktop computer, and they’re very large and can keep a computer running for minutes or hours!
 |
Want to know more? Watch “Motherboard Overview.”Every CompTIA A+ professional needs to have a complete understanding of motherboards and the components that reside on today’s PC motherboard technology. In this video, we’ll provide you with the information you need to instantly identify the most important motherboard features, and you’ll learn how chipset architectures relate to real-world motherboard configurations. |