Asus A7V8X-MXSE 1.10.1 Configuring an expansion card, Standard Interrupt Assignments, IRQ assignments for this motherboard

1.10 Expansion slots

The A7V8X-MX SE motherboard has three (3) PCI slots and one (1) Accelerated Graphics Port (AGP). The following sub-sections describe the slots and the expansion cards that they support.

1.10.1 Configuring an expansion card

Some expansion cards need an IRQ to operate. Generally, an IRQ must be exclusively assigned to one function at a time. In a standard design configuration, 16 IRQs are available but most are already in use.

Normally, 6 IRQs are free for expansion cards. Sometimes IRQs are “shared” by more than one function; in this case, IRQ assignments are swapped automatically or adjusted through the BIOS firmware.

Standard Interrupt Assignments

IRQ	Standard Function
0	System Timer
1	Keyboard Controller
2	Programmable Interrupt Controller
3*	USB Universal Host Controller
4*	Communications Port (COM1)
5*	Onboard Audio
6	Standard Floppy Disk Controller
7*	Printer Port (LPT1)
8	System CMOS/Real Time Clock
9*	Onboard LAN
10*	USB Universal Host Controller
11*	Onboard VGA
12*	PS/2 Compatible Mouse Port
13	Numeric Data Processor
14*	Ultra ATA Controller
15*	Secondary Ultra ATA Controller

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

IRQ assignments for this motherboard

	A	B	C
PCI slot 1	shared	––	––
PCI slot 2	––	shared	––
PCI slot 3	––	––	shared
AGP slot	shared	––	––

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