MSI G52-MA00542 - Manual (Page 38)

Chapter 2
2-26
CNR (Communication Network Riser)
The CNR slot allows you to insert the CNR expansion cards. CNR is a
specially designed network, audio, or modem riser card for ATX family
motherboards. Its main processing is done through software and controlled by
the motherboard’s chipset.
PCI Interrupt Request Routing
The IRQ, abbreviation of interrupt request line and pronounced I-R-Q,
are hardware lines over which devices can send interrupt signals to the
microprocessor. The PCI IRQ pins are typically connected to the PCI bus INT
A# ~ INT D# pins as follows:
Order 1 Order 2 Order 3 Order 4
PCI Slot 1 INT B# INT C# INT D# INT A#
PCI Slot 2 INT C# INT D# INT A# INT B#
PCI Slot 3 INT D# INT A# INT B# INT C#