Asus P5N-MX - Manual (Page 34)

1-22 Chapter 1: Product introduction
1.8.3 Interrupt assignments
Standard interrupt assignments
IRQ Standard Function
0 High precision event timer
1 Standard 101/102-key or Microsoft PS/2 keyboard
4 Communicators Port (COM1)
6 Standard floppy disk controller
8 High precision event timer
9 Microsoft ACPI-Compliant System
12 PS/2 Compatible Mouse
13 Numeric data processor
11 NVIDIA nForce PCI System Management
20 Standard OpenHCD USB Host Controller
21 Microsoft UAA Bus Driver for High Definition Audio
21 Standard Dual Channel PCI IDE Controller
22 NVIDIA GeForce 7050 / nForce 610i
22 Standard Enhanced PCI to USB Host Controller
23 NVIDIA Network Bus Enumerator
* These IRQs are usually available for ISA or PCI devices.