MSI MS-6555 Manual page 54

Chapter 3
Reload Global Timer Events: Primary/Secondary Master/Slave IDE, FDC/
LPT/COM Ports
Global Timer Events are I/O events whose occurrence can prevent the system
from entering a power saving mode or can awaken the system from such a
mode. In effect, the system remains alert for anything which occurs to a device
that is configured as Enabled, even when the system is in a power down mode.
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