A computer stores many basic hardware configuration details in a memory bank known as the CMOS. Sometimes the values in a CMOS become corrupt, causing your computer to stall during the boot-up process. If this happens, you won't be allowed to enter the BIOS to change the corrupted settings or load your operating system. Your computer will appear dead. Luckily, you can clear out the CMOS and restore its default settings. The CMOS requires electricity to maintain its memory. By cutting off its electricity, you can clear the CMOS and reset it.
Instructions
1. Remove the power cable from the computer.
2. Open up the computer case by unscrewing the case panel and sliding it off.
3. Locate the motherboard battery. The motherboard is the largest board in the computer, and it contains the CPU, RAM and expansion cards. The battery is a small, round disk about the size of a quarter.
4. Remove the motherboard battery.
5. Wait 30 seconds. The CMOS loses its charge, and all its configuration values are lost.
6. Plug the motherboard battery back in.
7. Replace the case door.
8. Plug in the power cable.
Tags: motherboard battery, clear CMOS, power cable