Standard interrupt assignments

IRQ

Priority

Standard Function

0

1

System Timer

1

2

Keyboard Controller

2

N/A

Programmable Interrupt

3*

11

Communications Port (COM2)

4*

12

Communications Port (COM1)

5*

13

IRQ holder for PCI steering

6

14

Floppy Disk Controller

7*

15

Printer Port (LPT1)

8

3

System CMOS/Real Time Clock

9*

4

IRQ holder for PCI steering

10*

5

Advance AC’97 CODEC

11*

6

Standard PCI Graphics Adapter (VGA)

12*

7

PS/2 Compatible Mouse Port

13

8

Numeric Data Processor

14*

9

Primary IDE Channel

15*

10

Secondary IDE Channel

*These IRQs are usually available for ISA or PCI devices.

IRQ assignments for this motherboard

 

A

B

C

D

E

F

G

H

PCI slot 1

—

used

—

—

—

—

—

—

PCI slot 2

—

—

shared

—

—

—

—

—

PCI slot 3

—

—

—

shared

—

—

—

—

AGP slot

shared

—

—

—

—

—

—

—

Onboard USB controller 1

—

—

—

—

used

—

—

—

Onboard USB controller 2

—

—

—

—

—

used

—

—

Onboard USB controller 3

—

—

—

—

—

—

used

—

Onboard USB 2.0 controller

—

—

—

—

—

—

—

used

Onboard LAN

—

—

—

shared

—

—

—

—

Onboard audio

—

—

shared

—

—

—

—

—

Onboard VGA

shared

—

—

—

—

—

—

—

When using PCI cards on shared slots, ensure that the drivers support “Share IRQ” or that the cards do not need IRQ assignments. Otherwise, conflicts will arise between the two PCI groups, making the system unstable and the card inoperable.

ASUS P4SP-MX motherboard user guide

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