ASROCK Z370 Extreme4 Handbuch Seite 22

2.5 Jumpers Setup
The illustration shows how jumpers are setup. When the jumper cap is placed on
the pins, the jumper is "Short". If no jumper cap is placed on the pins, the jumper is
"Open".
Clear CMOS Jumper
(CLRCMOS1)
(see p.1, No. 25)
CLRCMOS1 allows you to clear the data in CMOS. The data in CMOS includes
system setup information such as system password, date, time, and system setup
parameters. To clear and reset the system parameters to default setup, please
turn off the computer and unplug the power cord, then use a jumper cap to short
the pins on CLRCMOS1 for 3 seconds. Please remember to remove the jumper
cap after clearing the CMOS. If you need to clear the CMOS when you just finish
updating the BIOS, you must boot up the system first, and then shut it down
before you do the clear-CMOS action.
20
Short: Clear CMOS
Open: Default
2-pin Jumper