MSI G31TM-P21 - Motherboard - Micro ATX User Manual page 19

Chassis intrusion Connector: JCi
this connector connects to the chassis intrusion switch cable. if the chassis is
opened, the chassis intrusion mechanism will be activated. the system will record
this status and show a warning message on the screen. to clear the warning, you
must enter the BioS utility and clear the record.
Parallel Port Header: JLPt
this connector is used to connect an optional parallel port bracket. the parallel
port is a standard printer port that supports enhanced Parallel Port (ePP) and
extended Capabilities Parallel Port (eCP) mode.
aPS Led Status indicator: Led2 (optional)
the aPS (active Phase Switching) Led indicates the current CPu power phase
mode. Follow tthe instructions belows to read.
: on
Led2 will light blue when CPu is in 2 or 3 phase power mode.
Led2 will dark when CPu is in  phase power mode.
Led2
: oFF
MS-7529
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