Socket Mobile Pentium 4 Full Size PICMG CPU Card IB810 - Manual (Page 50)

BIOS SETUP
46 IB810 User’s Manual
Reload Global Timer Events
The HDD, FDD, COM, LPT Ports, and PCI PIRQ are I/O events which
can prevent the system from entering a power saving mode or can awaken
the system from such a mode. When an I/O device wants to gain the
attention of the operating system, it signals this by causing an IRQ to
occur. When the operating system is ready to respond to the request, it
interrupts itself and performs the service.