MSI MS-6120 Manual page 21

A battery must be used to retain the mainboard configuration in CMOS
RAM. You must short 1-2 pins of JBAT1 to keep the CMOS data.
Note: You can clear CMOS by shorting 2-3 pin, while the system is off.
Then, return to 1-2 pin position. To be able to clear the CMOS, you
need to unplug the power plug of the system, because there's a 3V
standby power for PIIX4E chipset which is provided by the power
supply. Otherwise, the CMOS will not be cleared.
JBAT1
1
3
1
3
2-17
1
3
JBAT1
Function
Keep Data
Clear Data