Gigabyte GA-Z77X-UP5 TH rev. 1.0 User Manual page 51

PC Health Status
Reset Case Open Status
Disabled Keeps or clears the record of previous chassis intrusion status. (Default)
Enabled Clears the record of previous chassis intrusion status and the Case Open
"No" at next boot.
Case Open
Displays the detection status of the chassis intrusion detection device attached to the motherboard CI
clear the chassis intrusion status record, set Reset Case Open Status to Enabled, save the settings to
the CMOS, and then restart your system.
BIOS Setup - 50 -