What does the clear CMOS jumper do?
A. It resets the BIOS to factory default settings and erases all system configuration data stored in CMOS. It is important to clear the CMOS before flashing the BIOS. Failure to clear CMOS can corrupt the bios and leave you with a disabled system until you can get a new BIOS chip. Sometimes after a BIOS update you must still clear the CMOS.