MSI MS-6334 Manual page 28

The JMDM1 connector is for used with Modem add-on card that supports
the Modem Wake Up function. To use this function, you need to set the
"Power On by Ring" to enable at the BIOS Power Management Setup.
JMDM1
Note: Modem wake-up signal is active "low".
Note: To be able to use this function, you need a power supply that
provide enough power for this feature. (Power supply with 750mA
5V Stand-by)
1
5
PIN
1
2
3
4
5
2-23
SIGNAL
NC
GND
MDM_WAKEUP
NC
5VSB