MSI G4m-P23 User Manual page 21

PCi express Slot
the PCi express slot supports the PCi express interface expansion card.
PCi Slot
the PCi slot supports Lan card, SCSi card, uSB card, and other add-on cards
that comply with PCi specifications.
imPoRtant
When adding or removing expansion cards, make sure that you unplug the power
supply first. meanwhile, read the documentation for the expansion card to config-
ure any necessary hardware or software settings for the expansion card, such as
jumpers, switches or BioS configuration.
PCi interrupt Request Routing
the iRq, acronym 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 pins as follows:
order
Slot
PCi 
PCi express x6 slot.
PCi express x slot.
 2
int a# int B#
3 4
int C# int d#
MS-7592
2